From 941c42bb626881523fb37c8737d6748de9707cae Mon Sep 17 00:00:00 2001
From: Abhijeet Prasad <abhijeet@braintrustdata.com>
Date: Fri, 4 Sep 2026 14:17:06 -0400
Subject: [PATCH] fix(adk): preserve agent spans for custom roots

Trace `BaseAgent.run_async` instead of treating `BaseNode.run` as its replacement.
---
 .agents/skills/commit-message/SKILL.md        | 200 ++++++++++++------
 py/pyproject.toml                             |   1 +
 ...base_agent_root_preserves_agent_spans.yaml |  57 +++++
 ...adk_binary_data_attachment_conversion.yaml |  58 +++++
 .../test_adk_braintrust_integration.yaml      | 126 +++++++++++
 .../2.6.3/test_adk_captures_metrics.yaml      |  56 +++++
 .../2.6.3/test_adk_complex_nested_schema.yaml |  68 ++++++
 ...base_agent_root_preserves_agent_spans.yaml |  57 +++++
 .../test_adk_input_schema_serialization.yaml  |  56 +++++
 .../test_adk_max_tokens_captures_content.yaml |  60 ++++++
 ...test_adk_multi_turn_history_is_logged.yaml | 114 ++++++++++
 ...nested_subagent_tool_calls_are_traced.yaml | 126 +++++++++++
 .../test_adk_response_json_schema_dict.yaml   |  61 ++++++
 .../test_adk_structured_output_pydantic.yaml  |  60 ++++++
 ..._transfer_does_not_log_generator_exit.yaml | 152 +++++++++++++
 ...n_does_not_duplicate_invocation_spans.yaml | 126 +++++++++++
 .../test_adk_usage_metadata_metrics.yaml      | 135 ++++++++++++
 ...base_agent_root_preserves_agent_spans.yaml |  62 ++++++
 .../integrations/adk/integration.py           |   2 -
 .../braintrust/integrations/adk/patchers.py   |  13 +-
 .../braintrust/integrations/adk/test_adk.py   |  67 +++++-
 py/src/braintrust/integrations/adk/tracing.py |  35 +--
 .../auto_test_scripts/test_auto_adk.py        |  10 +-
 23 files changed, 1590 insertions(+), 112 deletions(-)
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/1.14.1/test_adk_custom_base_agent_root_preserves_agent_spans.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_binary_data_attachment_conversion.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_braintrust_integration.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_captures_metrics.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_complex_nested_schema.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_custom_base_agent_root_preserves_agent_spans.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_input_schema_serialization.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_max_tokens_captures_content.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_multi_turn_history_is_logged.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_nested_subagent_tool_calls_are_traced.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_response_json_schema_dict.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_structured_output_pydantic.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_subagent_transfer_does_not_log_generator_exit.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_sync_runner_run_does_not_duplicate_invocation_spans.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_usage_metadata_metrics.yaml
 create mode 100644 py/src/braintrust/integrations/adk/cassettes/latest/test_adk_custom_base_agent_root_preserves_agent_spans.yaml

diff --git a/.agents/skills/commit-message/SKILL.md b/.agents/skills/commit-message/SKILL.md
index e9e160d74..6a44ebf09 100644
--- a/.agents/skills/commit-message/SKILL.md
+++ b/.agents/skills/commit-message/SKILL.md
@@ -1,97 +1,169 @@
 ---
 name: commit-message
-description: Suggest a Braintrust SDK repo-style commit message from the current diff and conversation. Use when asked to write, suggest, or generate a commit message for the current changes.
+description: Generates a meaningful conventional commit message (title + body) from the current diff and conversation context. Use when asked to write, suggest, or generate a commit message for the current changes.
 ---
 
-# Commit Message
+# Commit Message Generator
 
-Generate a single commit message that matches the style used on `main` in this repo.
+Generate a conventional commit message based on the staged/unstaged diff and the surrounding conversation.
 
-## Repo Style
+## Conventional Commits Format
 
-Prefer:
+```
+<type>(<scope>): <short summary>
+
+<body>
 
-```text
-<type>(<scope>): <summary>
+<footer>
 ```
 
-or, when scope does not add much:
+**Types:**
+- `feat` — new feature
+- `fix` — bug fix
+- `ref` — code restructuring without behavior change (prefer `ref` over `refactor`)
+- `perf` — performance improvement
+- `test` — adding or updating tests
+- `docs` — documentation only
+- `chore` — build system, tooling, dependencies, config
+- `ci` — CI/CD pipeline changes
+- `style` — formatting, whitespace (no logic change)
+- `revert` — reverts a previous commit
+
+**Rules:**
+- Subject line ≤ 72 characters, lowercase, no trailing period
+- Imperative mood: "add feature" not "added feature"
+- Body wraps at 100 characters, explains *what* and *why* (not *how*)
+- Footer: `BREAKING CHANGE: ...` or `Fixes #<issue>` / `Closes #<issue>` if applicable
+- Scope is optional but encouraged when it adds clarity (e.g., `feat(auth):`, `fix(api):`)
+- Omit body if the subject line fully communicates the intent
+
+## Writing Style
+
+- Lead with the point. Be direct, technical, collaborative, and lightly casual.
+- Use plain words, contractions where natural, and short paragraphs.
+- Prefer `we` for shared decisions and `I` for genuine opinion or uncertainty. Do not hide uncertainty behind authoritative prose.
+- Ground claims in specifics: name the API, version, behavior, error, test, or file involved.
+- Put code, identifiers, filenames, versions, and literal values in backticks.
+- Give only the context needed to explain **context → change → reason/evidence → consequence or follow-up**.
+- Surface compatibility constraints, tradeoffs, risks, and intentionally deferred work plainly when relevant.
+- Use bullets for multiple distinct changes or findings; avoid unnecessary headings and polished filler.
+- Do not merely restate the diff. Explain why the implementation matters or how behavior changes.
+
+For a substantive change, actively consider including a compact code snippet, before/after example, or ASCII diagram when it explains behavior or data flow more clearly than prose. Keep it focused and omit it when it would be decorative or redundant. For example:
+
+````text
+Before: provider response -> wrapper-specific span
+After:  provider response -> shared integration hook -> normalized span
+````
+
+or:
+
+````python
+# Before
+wrap(client)
+
+# After
+client = wrap_client(client)
+````
+
+## Instructions
+
+1. **Collect the diff** — run `git diff HEAD` (staged + unstaged). If empty, try `git diff --cached` (staged only). If still empty, try `git status --short` and `git log --oneline -3` to understand the trajectory.
+
+2. **Review the conversation** — you already have the conversation history in context. Look for:
+   - Explicit intent from the user ("I'm adding X", "this fixes Y")
+   - Issue or ticket numbers mentioned
+   - Feature names, module names, or domain language used
+   - Any constraints or things the user emphasized
+
+3. **Identify ambiguities** — before generating, check if any of these are unclear:
+   - Is the primary intent a new feature, a fix, a refactor, or something else?
+   - Is there a scope (module/package/component) worth calling out?
+   - Are there breaking changes?
+   - Is there a related issue or ticket number?
+   - Does the diff span multiple unrelated concerns? (should be split into separate commits)
+
+4. **Ask for clarifications if needed** — if the intent is genuinely ambiguous from both the diff and the conversation, ask 1–3 focused questions before generating. Do **not** ask about things already clear from the context.
+
+5. **Generate the commit message** — produce exactly one commit message in a fenced code block:
+   - Pick the most specific `type` that fits
+   - Include a `scope` when it meaningfully narrows the change
+   - Write a crisp subject line in imperative mood
+   - Add a body if the change is non-trivial, explaining the reasoning
+   - Check whether a small before/after snippet or ASCII diagram would make a substantive change easier to review, and include one when it would
+   - Add footer entries for breaking changes or issue references
+   - **CRITICAL when committing:** preserve **real newline characters** in the commit body
+   - **Never** put literal `\n` text inside a quoted `git commit -m "..."` body and assume Git will turn it into line breaks — it will not
+   - If issuing `git commit` yourself, prefer these patterns in this order:
+     1. **Best for multiline bodies:** write the full message to a temp file and use `git commit -F <file>`
+     2. **Good for amendments:** write the full message to a temp file and use `git commit --amend -F <file>`
+     3. multiple `-m` flags, e.g. `git commit -m "subject" -m "first paragraph
+
+second paragraph"`
+     4. ANSI-C quoting, e.g. `git commit -m "subject" -m $'line 1\n\nline 2'`
+   - Prefer temp-file commits by default whenever the body has multiple paragraphs, bullets, or any non-trivial formatting
+   - Before finalizing, sanity-check that `git log -1 --format=medium` shows actual blank lines and wrapped paragraphs, not backslash-n sequences
+
+## Newline safety examples
+
+**Wrong:**
 
-```text
-<type>: <summary>
+```bash
+git commit -m "docs: add pi guide" -m "line 1\n\nline 2"
 ```
 
-Recent `main` examples:
+This stores the characters `\` and `n` literally in the commit message.
 
-- `feat(openai): trace images api calls`
-- `fix(framework): split \`Output\` TypeVar into \`Output\` and \`Expected\``
-- `ref(litellm): migrate litellm wrapper to integrations API`
-- `chore: generated SDK types`
-- `ci(checks): bump nox shards to 4 and introduce shard weights`
-- `test(openai): add vcr regression coverage for stream helpers`
-- `docs: document integrations in readme`
-- `perf(json): reduce span serialization overhead`
+**Correct:**
 
-Notes:
+```bash
+git commit -m "docs: add pi guide" -m $'line 1\n\nline 2'
+```
 
-- This repo uses `ref`, not `refactor`.
-- Scope is common and usually names the subsystem, provider, or area being changed.
-- Commits on `main` often include a GitHub squash suffix like `(#245)`. Omit that for a normal local commit unless the user explicitly wants a PR title or squash-merge title.
-- This repo commonly uses commit bodies for substantive changes. Prefer a concise subject that makes the main change obvious, and add a short body unless the change is truly trivial and fully explained by the subject.
+or
 
-## Types
+```bash
+git commit -m "docs: add pi guide" -m "line 1
 
-Use the most specific type:
+line 2"
+```
 
-- `feat` — new feature
-- `fix` — bug fix
-- `ref` — restructuring without behavior change
-- `perf` — performance improvement
-- `test` — tests only
-- `docs` — documentation only
-- `chore` — tooling, generated files, maintenance, config
-- `ci` — GitHub Actions, nox sharding, CI wiring
-- `style` — formatting only
-- `revert` — reverting a prior change
+or use a temp file/editor.
 
-## Scope Guidance
+## Default execution preference
 
-Good scopes in this repo usually look like:
+When the task is not just to suggest a commit message, but to actually run `git commit` or `git commit --amend`:
 
-- provider or integration names: `openai`, `anthropic`, `google_genai`, `claude_agent_sdk`, `langchain`
-- SDK areas: `framework`, `cli`, `devserver`, `integrations`
-- CI/tooling areas: `checks`, `nox`, `release`
+1. If the message has a body, prefer a temp file with `-F`
+2. If amending a commit with a body, prefer `git commit --amend -F <file>`
+3. Only use inline `-m` bodies when the formatting is trivially simple and you are certain real newlines will be preserved
+4. After committing, verify with `git log -1 --format=medium`
 
-If the change is broad or generated, omit scope instead of forcing one.
+This preference exists to avoid malformed commit bodies with literal `\n` sequences.
 
-## Rules
+## Output Format
 
-- Keep the message useful but concise.
-- Keep the subject concise and imperative.
-- Prefer lowercase style and no trailing period.
-- Keep the subject around 72 characters or less when practical.
-- Describe the primary change, not every file touched.
-- Make the subject specific enough that a reviewer can understand the change without opening the diff.
-- If the diff mixes unrelated concerns, say so instead of forcing one message.
-- Add a short body by default for feature, fix, perf, or ref commits.
-- The body should briefly capture why the change was made, any important behavioral detail, and key test/coverage notes when they materially help a reviewer.
-- Only omit the body when the change is truly tiny and the subject fully explains it.
+Present the final message in a fenced code block. If the message contains its own fenced snippet, use a longer outer fence so the full message remains copyable:
 
-## Workflow
+```
+feat(auth): add OAuth2 PKCE flow for CLI login
 
-1. Inspect the current change:
+Replace the device-code flow with PKCE so the CLI can authenticate
+without opening a browser on headless machines. The previous flow
+required interactive browser consent which blocked CI usage.
 
-```bash
-git diff HEAD
-git diff --cached
-git status --short
+Closes #342
 ```
 
-2. Pick the main intent, choose `type` and optional `scope`, then write one useful but concise commit message.
-3. Unless the change is trivial, include a body with 1-3 short paragraphs or bullets covering rationale, behavior, or test coverage.
+Then briefly (1–2 sentences) explain the key decision made (type choice, scope, whether a body was needed).
 
-## Output
+If you asked for clarifications and the user answered, incorporate those answers and output the final message immediately — no need to re-ask.
 
-Return exactly one commit message in a fenced code block.
+## Commands
 
-If helpful, add one short sentence after the block explaining the type/scope choice.
+```bash
+git diff HEAD
+git diff --cached
+git status --short
+git log --oneline -5
+```
diff --git a/py/pyproject.toml b/py/pyproject.toml
index e1984dfbf..cf16e9431 100644
--- a/py/pyproject.toml
+++ b/py/pyproject.toml
@@ -479,6 +479,7 @@ latest = "crewai==1.15.18"
 
 [tool.braintrust.matrix.google-adk]
 latest = "google-adk[mcp]==2.8.0"
+"2.6.3" = "google-adk[mcp]==2.6.3"
 "1.14.1" = "google-adk[mcp]==1.14.1"
 
 [tool.braintrust.matrix.langchain-core]
diff --git a/py/src/braintrust/integrations/adk/cassettes/1.14.1/test_adk_custom_base_agent_root_preserves_agent_spans.yaml b/py/src/braintrust/integrations/adk/cassettes/1.14.1/test_adk_custom_base_agent_root_preserves_agent_spans.yaml
new file mode 100644
index 000000000..e2662d861
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/1.14.1/test_adk_custom_base_agent_root_preserves_agent_spans.yaml
@@ -0,0 +1,57 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"text": "Say hello."}], "role": "user"}, {"parts":
+      [{"text": "For context:"}, {"text": "[custom_root] said: step"}], "role": "user"}],
+      "systemInstruction": {"parts": [{"text": "Reply with only the word hello.\n\nYou
+      are an agent. Your internal name is \"child\"."}], "role": "user"}, "generationConfig":
+      {}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
+      - google-genai-sdk/1.75.0 gl-python/3.14.6 google-adk/1.14.1 gl-python/3.14.6
+      x-goog-api-client:
+      - google-genai-sdk/1.75.0 gl-python/3.14.6 google-adk/1.14.1 gl-python/3.14.6
+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"text\": \"hello\"\n          }\n        ],\n
+        \       \"role\": \"model\"\n      },\n      \"finishReason\": \"STOP\",\n
+        \     \"index\": 0\n    }\n  ],\n  \"usageMetadata\": {\n    \"promptTokenCount\":
+        37,\n    \"candidatesTokenCount\": 1,\n    \"totalTokenCount\": 38,\n    \"promptTokensDetails\":
+        [\n      {\n        \"modality\": \"TEXT\",\n        \"tokenCount\": 37\n
+        \     }\n    ],\n    \"serviceTier\": \"standard\"\n  },\n  \"modelVersion\":
+        \"gemini-2.5-flash-lite\",\n  \"responseId\": \"5vyaatfQE_3A39IPhsvziAE\"\n}\n"
+    headers:
+      Alt-Svc:
+      - h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+      Content-Type:
+      - application/json; charset=UTF-8
+      Date:
+      - Fri, 04 Sep 2026 17:16:22 GMT
+      Server:
+      - scaffolding on HTTPServer2
+      Server-Timing:
+      - gfet4t7; dur=362
+      Transfer-Encoding:
+      - chunked
+      Vary:
+      - Origin
+      - X-Origin
+      - Referer
+      X-Content-Type-Options:
+      - nosniff
+      X-Frame-Options:
+      - SAMEORIGIN
+      X-Gemini-Service-Tier:
+      - standard
+      X-XSS-Protection:
+      - '0'
+      content-length:
+      - '552'
+    status:
+      code: 200
+      message: OK
+version: 1
diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_binary_data_attachment_conversion.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_binary_data_attachment_conversion.yaml
new file mode 100644
index 000000000..4ad05c3a1
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_binary_data_attachment_conversion.yaml
@@ -0,0 +1,58 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"inlineData": {"data": "iVBORw0KGgoAAAANSUhEUgAAAAoAAAAKCAYAAACNMs-9AAAAFElEQVR42mP4z8DwnxjMMKqQvgoBksPHOXvuG4oAAAAASUVORK5CYII=",
+      "mimeType": "image/png"}}, {"text": "What color is this image?"}], "role": "user"}],
+      "systemInstruction": {"parts": [{"text": "You are a helpful assistant that can
+      analyze images.\n\nYou are an agent. Your internal name is \"vision_agent\"."}],
+      "role": "user"}, "generationConfig": {"maxOutputTokens": 150}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+      x-goog-api-client:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"text\": \"The image is red.\"\n          }\n
+        \       ],\n        \"role\": \"model\"\n      },\n      \"finishReason\":
+        \"STOP\",\n      \"index\": 0\n    }\n  ],\n  \"usageMetadata\": {\n    \"promptTokenCount\":
+        291,\n    \"candidatesTokenCount\": 5,\n    \"totalTokenCount\": 296,\n    \"promptTokensDetails\":
+        [\n      {\n        \"modality\": \"TEXT\",\n        \"tokenCount\": 33\n
+        \     },\n      {\n        \"modality\": \"IMAGE\",\n        \"tokenCount\":
+        258\n      }\n    ],\n    \"serviceTier\": \"standard\"\n  },\n  \"modelVersion\":
+        \"gemini-2.5-flash-lite\",\n  \"responseId\": \"W_yaav_8LIOl1MkPq_u00Q8\"\n}\n"
+    headers:
+      Alt-Svc:
+      - h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+      Content-Type:
+      - application/json; charset=UTF-8
+      Date:
+      - Fri, 04 Sep 2026 17:14:04 GMT
+      Server:
+      - scaffolding on HTTPServer2
+      Server-Timing:
+      - gfet4t7; dur=399
+      Transfer-Encoding:
+      - chunked
+      Vary:
+      - Origin
+      - X-Origin
+      - Referer
+      X-Content-Type-Options:
+      - nosniff
+      X-Frame-Options:
+      - SAMEORIGIN
+      X-Gemini-Service-Tier:
+      - standard
+      X-XSS-Protection:
+      - '0'
+      content-length:
+      - '638'
+    status:
+      code: 200
+      message: OK
+version: 1
diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_braintrust_integration.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_braintrust_integration.yaml
new file mode 100644
index 000000000..f63ce4d56
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_braintrust_integration.yaml
@@ -0,0 +1,126 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"text": "What''s the weather in San Francisco?"}],
+      "role": "user"}], "systemInstruction": {"parts": [{"text": "You are a helpful
+      weather assistant. Use the get_weather tool to answer questions about weather.\n\nYou
+      are an agent. Your internal name is \"weather_agent\"."}], "role": "user"},
+      "tools": [{"functionDeclarations": [{"description": "Get the weather for a location.",
+      "name": "get_weather", "parameters_json_schema": {"properties": {"location":
+      {"title": "Location", "type": "string"}}, "required": ["location"], "title":
+      "get_weatherParams", "type": "object"}}]}], "generationConfig": {}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+      x-goog-api-client:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"functionCall\": {\n              \"name\": \"get_weather\",\n
+        \             \"args\": {\n                \"location\": \"San Francisco\"\n
+        \             }\n            }\n          }\n        ],\n        \"role\":
+        \"model\"\n      },\n      \"finishReason\": \"STOP\",\n      \"index\": 0,\n
+        \     \"finishMessage\": \"Model generated function call(s).\"\n    }\n  ],\n
+        \ \"usageMetadata\": {\n    \"promptTokenCount\": 84,\n    \"candidatesTokenCount\":
+        16,\n    \"totalTokenCount\": 100,\n    \"promptTokensDetails\": [\n      {\n
+        \       \"modality\": \"TEXT\",\n        \"tokenCount\": 84\n      }\n    ],\n
+        \   \"serviceTier\": \"standard\"\n  },\n  \"modelVersion\": \"gemini-2.5-flash-lite\",\n
+        \ \"responseId\": \"VvyaapWHH9zi_uMPhKDNmQ0\"\n}\n"
+    headers:
+      Alt-Svc:
+      - h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+      Content-Type:
+      - application/json; charset=UTF-8
+      Date:
+      - Fri, 04 Sep 2026 17:13:58 GMT
+      Server:
+      - scaffolding on HTTPServer2
+      Server-Timing:
+      - gfet4t7; dur=339
+      Transfer-Encoding:
+      - chunked
+      Vary:
+      - Origin
+      - X-Origin
+      - Referer
+      X-Content-Type-Options:
+      - nosniff
+      X-Frame-Options:
+      - SAMEORIGIN
+      X-Gemini-Service-Tier:
+      - standard
+      X-XSS-Protection:
+      - '0'
+      content-length:
+      - '751'
+    status:
+      code: 200
+      message: OK
+- request:
+    body: '{"contents": [{"parts": [{"text": "What''s the weather in San Francisco?"}],
+      "role": "user"}, {"parts": [{"functionCall": {"args": {"location": "San Francisco"},
+      "name": "get_weather"}}], "role": "model"}, {"parts": [{"functionResponse":
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+      "72\u00b0F", "condition": "sunny", "humidity": "45%", "wind": "5 mph NW"}}}],
+      "role": "user"}], "systemInstruction": {"parts": [{"text": "You are a helpful
+      weather assistant. Use the get_weather tool to answer questions about weather.\n\nYou
+      are an agent. Your internal name is \"weather_agent\"."}], "role": "user"},
+      "tools": [{"functionDeclarations": [{"description": "Get the weather for a location.",
+      "name": "get_weather", "parameters_json_schema": {"properties": {"location":
+      {"title": "Location", "type": "string"}}, "required": ["location"], "title":
+      "get_weatherParams", "type": "object"}}]}], "generationConfig": {}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
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+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
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+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
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+    headers:
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+    status:
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+      message: OK
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diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_captures_metrics.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_captures_metrics.yaml
new file mode 100644
index 000000000..56a912ab1
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_captures_metrics.yaml
@@ -0,0 +1,56 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"text": "Say hello in 3 words"}], "role": "user"}],
+      "systemInstruction": {"parts": [{"text": "You are a helpful assistant.\n\nYou
+      are an agent. Your internal name is \"metrics_agent\"."}], "role": "user"},
+      "generationConfig": {}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
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+      x-goog-api-client:
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+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"text\": \"Hello there, friend.\"\n          }\n
+        \       ],\n        \"role\": \"model\"\n      },\n      \"finishReason\":
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+    headers:
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+      - '0'
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+    status:
+      code: 200
+      message: OK
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diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_complex_nested_schema.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_complex_nested_schema.yaml
new file mode 100644
index 000000000..1d84e32ff
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_complex_nested_schema.yaml
@@ -0,0 +1,68 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"text": "Give me info about Alice who lives in
+      Paris, France."}], "role": "user"}], "systemInstruction": {"parts": [{"text":
+      "Return a person with their address.\n\nYou are an agent. Your internal name
+      is \"nested_agent\"."}], "role": "user"}, "generationConfig": {"responseMimeType":
+      "application/json", "responseSchema": {"properties": {"name": {"description":
+      "Person''s name", "title": "Name", "type": "STRING"}, "age": {"description":
+      "Person''s age", "maximum": 150.0, "minimum": 0.0, "title": "Age", "type": "INTEGER"},
+      "address": {"properties": {"street": {"description": "Street address", "title":
+      "Street", "type": "STRING"}, "city": {"description": "City name", "title": "City",
+      "type": "STRING"}, "country": {"description": "Country name", "title": "Country",
+      "type": "STRING"}}, "property_ordering": ["street", "city", "country"], "required":
+      ["street", "city", "country"], "title": "Address", "type": "OBJECT"}}, "property_ordering":
+      ["name", "age", "address"], "required": ["name", "age", "address"], "title":
+      "Person", "type": "OBJECT"}}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
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+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
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+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
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+        \ },\n  \"modelVersion\": \"gemini-2.5-flash-lite\",\n  \"responseId\": \"YfyaaolSia_89Q-R6rnoBg\"\n}\n"
+    headers:
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diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_custom_base_agent_root_preserves_agent_spans.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_custom_base_agent_root_preserves_agent_spans.yaml
new file mode 100644
index 000000000..bb56d464a
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_custom_base_agent_root_preserves_agent_spans.yaml
@@ -0,0 +1,57 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"text": "Say hello."}], "role": "user"}, {"parts":
+      [{"text": "For context:"}, {"text": "[custom_root] said: step"}], "role": "user"}],
+      "systemInstruction": {"parts": [{"text": "Reply with only the word hello.\n\nYou
+      are an agent. Your internal name is \"child\"."}], "role": "user"}, "generationConfig":
+      {}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
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+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"text\": \"hello\"\n          }\n        ],\n
+        \       \"role\": \"model\"\n      },\n      \"finishReason\": \"STOP\",\n
+        \     \"index\": 0\n    }\n  ],\n  \"usageMetadata\": {\n    \"promptTokenCount\":
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+        \     }\n    ],\n    \"serviceTier\": \"standard\"\n  },\n  \"modelVersion\":
+        \"gemini-2.5-flash-lite\",\n  \"responseId\": \"F_2aauCeNdvU_uMPkNPziQE\"\n}\n"
+    headers:
+      Alt-Svc:
+      - h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+      Content-Type:
+      - application/json; charset=UTF-8
+      Date:
+      - Fri, 04 Sep 2026 17:17:12 GMT
+      Server:
+      - scaffolding on HTTPServer2
+      Server-Timing:
+      - gfet4t7; dur=413
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+    status:
+      code: 200
+      message: OK
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diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_input_schema_serialization.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_input_schema_serialization.yaml
new file mode 100644
index 000000000..830e24f83
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_input_schema_serialization.yaml
@@ -0,0 +1,56 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"text": "{\"name\":\"Alice\",\"age\":30}"}],
+      "role": "user"}], "systemInstruction": {"parts": [{"text": "You are a test agent
+      with input schema.\n\nYou are an agent. Your internal name is \"input_schema_agent\"."}],
+      "role": "user"}, "generationConfig": {}}'
+    headers:
+      Content-Type:
+      - application/json
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+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"text\": \"Please provide me with the input schema.\"\n
+        \         }\n        ],\n        \"role\": \"model\"\n      },\n      \"finishReason\":
+        \"STOP\",\n      \"index\": 0\n    }\n  ],\n  \"usageMetadata\": {\n    \"promptTokenCount\":
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+        \     }\n    ],\n    \"serviceTier\": \"standard\"\n  },\n  \"modelVersion\":
+        \"gemini-2.5-flash-lite\",\n  \"responseId\": \"YPyaasbEHrek_uMP1-WFuQg\"\n}\n"
+    headers:
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+      - '0'
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+      - '587'
+    status:
+      code: 200
+      message: OK
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diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_max_tokens_captures_content.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_max_tokens_captures_content.yaml
new file mode 100644
index 000000000..125b9940c
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_max_tokens_captures_content.yaml
@@ -0,0 +1,60 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"text": "Tell me a long story about a lighthouse."}],
+      "role": "user"}], "systemInstruction": {"parts": [{"text": "You are a creative
+      storyteller.\n\nYou are an agent. Your internal name is \"creative_agent\"."}],
+      "role": "user"}, "generationConfig": {"temperature": 0.7, "maxOutputTokens":
+      50}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
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+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"text\": \"The Saltwick Lighthouse stood on the
+        very edge of the world, or so it felt to the handful of souls who called its
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+    headers:
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+      message: OK
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diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_multi_turn_history_is_logged.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_multi_turn_history_is_logged.yaml
new file mode 100644
index 000000000..174572d83
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_multi_turn_history_is_logged.yaml
@@ -0,0 +1,114 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"text": "Hi, my name is Alice."}], "role": "user"}],
+      "systemInstruction": {"parts": [{"text": "You are a concise assistant. When
+      the user says their name, acknowledge it briefly. When later asked to recall
+      it, answer with just the name.\n\nYou are an agent. Your internal name is \"conversation_agent\"."}],
+      "role": "user"}, "generationConfig": {}}'
+    headers:
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+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
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+      {"parts": [{"text": "Hi Alice."}], "role": "model"}, {"parts": [{"text": "What
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+        66,\n    \"candidatesTokenCount\": 2,\n    \"totalTokenCount\": 68,\n    \"promptTokensDetails\":
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+        \     }\n    ],\n    \"serviceTier\": \"standard\"\n  },\n  \"modelVersion\":
+        \"gemini-2.5-flash-lite\",\n  \"responseId\": \"U_yaap7hOtvU_uMPkNPziQE\"\n}\n"
+    headers:
+      Alt-Svc:
+      - h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+      Content-Type:
+      - application/json; charset=UTF-8
+      Date:
+      - Fri, 04 Sep 2026 17:13:56 GMT
+      Server:
+      - scaffolding on HTTPServer2
+      Server-Timing:
+      - gfet4t7; dur=395
+      Transfer-Encoding:
+      - chunked
+      Vary:
+      - Origin
+      - X-Origin
+      - Referer
+      X-Content-Type-Options:
+      - nosniff
+      X-Frame-Options:
+      - SAMEORIGIN
+      X-Gemini-Service-Tier:
+      - standard
+      X-XSS-Protection:
+      - '0'
+      content-length:
+      - '553'
+    status:
+      code: 200
+      message: OK
+version: 1
diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_nested_subagent_tool_calls_are_traced.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_nested_subagent_tool_calls_are_traced.yaml
new file mode 100644
index 000000000..fc3801565
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_nested_subagent_tool_calls_are_traced.yaml
@@ -0,0 +1,126 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"text": "What''s the weather in San Francisco?"}],
+      "role": "user"}], "systemInstruction": {"parts": [{"text": "You are a helpful
+      weather assistant. Use the get_weather tool to answer questions about weather.\n\nYou
+      are an agent. Your internal name is \"weather_agent\"."}], "role": "user"},
+      "tools": [{"functionDeclarations": [{"description": "Get the weather for a location.",
+      "name": "get_weather", "parameters_json_schema": {"properties": {"location":
+      {"title": "Location", "type": "string"}}, "required": ["location"], "title":
+      "get_weatherParams", "type": "object"}}]}], "generationConfig": {}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+      x-goog-api-client:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"functionCall\": {\n              \"name\": \"get_weather\",\n
+        \             \"args\": {\n                \"location\": \"San Francisco\"\n
+        \             }\n            }\n          }\n        ],\n        \"role\":
+        \"model\"\n      },\n      \"finishReason\": \"STOP\",\n      \"index\": 0,\n
+        \     \"finishMessage\": \"Model generated function call(s).\"\n    }\n  ],\n
+        \ \"usageMetadata\": {\n    \"promptTokenCount\": 84,\n    \"candidatesTokenCount\":
+        16,\n    \"totalTokenCount\": 100,\n    \"promptTokensDetails\": [\n      {\n
+        \       \"modality\": \"TEXT\",\n        \"tokenCount\": 84\n      }\n    ],\n
+        \   \"serviceTier\": \"standard\"\n  },\n  \"modelVersion\": \"gemini-2.5-flash-lite\",\n
+        \ \"responseId\": \"WfyaarueGsfL_uMP2-vQoQE\"\n}\n"
+    headers:
+      Alt-Svc:
+      - h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+      Content-Type:
+      - application/json; charset=UTF-8
+      Date:
+      - Fri, 04 Sep 2026 17:14:01 GMT
+      Server:
+      - scaffolding on HTTPServer2
+      Server-Timing:
+      - gfet4t7; dur=266
+      Transfer-Encoding:
+      - chunked
+      Vary:
+      - Origin
+      - X-Origin
+      - Referer
+      X-Content-Type-Options:
+      - nosniff
+      X-Frame-Options:
+      - SAMEORIGIN
+      X-Gemini-Service-Tier:
+      - standard
+      X-XSS-Protection:
+      - '0'
+      content-length:
+      - '751'
+    status:
+      code: 200
+      message: OK
+- request:
+    body: '{"contents": [{"parts": [{"text": "What''s the weather in San Francisco?"}],
+      "role": "user"}, {"parts": [{"functionCall": {"args": {"location": "San Francisco"},
+      "name": "get_weather"}}], "role": "model"}, {"parts": [{"functionResponse":
+      {"name": "get_weather", "response": {"location": "San Francisco", "temperature":
+      "72\u00b0F", "condition": "sunny"}}}], "role": "user"}], "systemInstruction":
+      {"parts": [{"text": "You are a helpful weather assistant. Use the get_weather
+      tool to answer questions about weather.\n\nYou are an agent. Your internal name
+      is \"weather_agent\"."}], "role": "user"}, "tools": [{"functionDeclarations":
+      [{"description": "Get the weather for a location.", "name": "get_weather", "parameters_json_schema":
+      {"properties": {"location": {"title": "Location", "type": "string"}}, "required":
+      ["location"], "title": "get_weatherParams", "type": "object"}}]}], "generationConfig":
+      {}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+      x-goog-api-client:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"text\": \"The weather in San Francisco is sunny
+        with a temperature of 72\xB0F.\"\n          }\n        ],\n        \"role\":
+        \"model\"\n      },\n      \"finishReason\": \"STOP\",\n      \"index\": 0\n
+        \   }\n  ],\n  \"usageMetadata\": {\n    \"promptTokenCount\": 131,\n    \"candidatesTokenCount\":
+        17,\n    \"totalTokenCount\": 148,\n    \"promptTokensDetails\": [\n      {\n
+        \       \"modality\": \"TEXT\",\n        \"tokenCount\": 131\n      }\n    ],\n
+        \   \"serviceTier\": \"standard\"\n  },\n  \"modelVersion\": \"gemini-2.5-flash-lite\",\n
+        \ \"responseId\": \"WfyaaoWmN-ua9MoPjZzsoQQ\"\n}\n"
+    headers:
+      Alt-Svc:
+      - h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+      Content-Type:
+      - application/json; charset=UTF-8
+      Date:
+      - Fri, 04 Sep 2026 17:14:02 GMT
+      Server:
+      - scaffolding on HTTPServer2
+      Server-Timing:
+      - gfet4t7; dur=1098
+      Transfer-Encoding:
+      - chunked
+      Vary:
+      - Origin
+      - X-Origin
+      - Referer
+      X-Content-Type-Options:
+      - nosniff
+      X-Frame-Options:
+      - SAMEORIGIN
+      X-Gemini-Service-Tier:
+      - standard
+      X-XSS-Protection:
+      - '0'
+      content-length:
+      - '617'
+    status:
+      code: 200
+      message: OK
+version: 1
diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_response_json_schema_dict.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_response_json_schema_dict.yaml
new file mode 100644
index 000000000..e80dfde78
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_response_json_schema_dict.yaml
@@ -0,0 +1,61 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"text": "Tell me about Tokyo"}], "role": "user"}],
+      "systemInstruction": {"parts": [{"text": "You are a City Information Agent.
+      Provide city information.\n\nYou are an agent. Your internal name is \"city_agent\"."}],
+      "role": "user"}, "generationConfig": {"responseMimeType": "application/json",
+      "responseJsonSchema": {"type": "object", "properties": {"city": {"type": "string",
+      "description": "Name of the city"}, "population": {"type": "integer", "description":
+      "Population of the city", "minimum": 0}, "country": {"type": "string", "description":
+      "Country where the city is located"}}, "required": ["city", "country"]}}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+      x-goog-api-client:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"text\": \"{\\n  \\\"city\\\": \\\"Tokyo\\\",\\n
+        \ \\\"country\\\": \\\"Japan\\\"\\n}\"\n          }\n        ],\n        \"role\":
+        \"model\"\n      },\n      \"finishReason\": \"STOP\",\n      \"index\": 0\n
+        \   }\n  ],\n  \"usageMetadata\": {\n    \"promptTokenCount\": 32,\n    \"candidatesTokenCount\":
+        19,\n    \"totalTokenCount\": 51,\n    \"promptTokensDetails\": [\n      {\n
+        \       \"modality\": \"TEXT\",\n        \"tokenCount\": 32\n      }\n    ],\n
+        \   \"serviceTier\": \"standard\"\n  },\n  \"modelVersion\": \"gemini-2.5-flash-lite\",\n
+        \ \"responseId\": \"YfyaaqLCIsqi_uMPyLPLiAE\"\n}\n"
+    headers:
+      Alt-Svc:
+      - h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+      Content-Type:
+      - application/json; charset=UTF-8
+      Date:
+      - Fri, 04 Sep 2026 17:14:09 GMT
+      Server:
+      - scaffolding on HTTPServer2
+      Server-Timing:
+      - gfet4t7; dur=364
+      Transfer-Encoding:
+      - chunked
+      Vary:
+      - Origin
+      - X-Origin
+      - Referer
+      X-Content-Type-Options:
+      - nosniff
+      X-Frame-Options:
+      - SAMEORIGIN
+      X-Gemini-Service-Tier:
+      - standard
+      X-XSS-Protection:
+      - '0'
+      content-length:
+      - '602'
+    status:
+      code: 200
+      message: OK
+version: 1
diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_structured_output_pydantic.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_structured_output_pydantic.yaml
new file mode 100644
index 000000000..ff907d111
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_structured_output_pydantic.yaml
@@ -0,0 +1,60 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"text": "What is the capital of France?"}], "role":
+      "user"}], "systemInstruction": {"parts": [{"text": "You are a Capital Information
+      Agent. Given a country, respond ONLY with a JSON object containing the capital.
+      Format: {\"capital\": \"capital_name\"}\n\nYou are an agent. Your internal name
+      is \"capital_agent\"."}], "role": "user"}, "generationConfig": {"responseMimeType":
+      "application/json", "responseSchema": {"properties": {"capital": {"description":
+      "The capital of the country.", "title": "Capital", "type": "STRING"}}, "required":
+      ["capital"], "title": "CapitalOutput", "type": "OBJECT"}}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+      x-goog-api-client:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"text\": \"{\\\"capital\\\": \\\"Paris\\\"}\"\n
+        \         }\n        ],\n        \"role\": \"model\"\n      },\n      \"finishReason\":
+        \"STOP\",\n      \"index\": 0\n    }\n  ],\n  \"usageMetadata\": {\n    \"promptTokenCount\":
+        55,\n    \"candidatesTokenCount\": 6,\n    \"totalTokenCount\": 61,\n    \"promptTokensDetails\":
+        [\n      {\n        \"modality\": \"TEXT\",\n        \"tokenCount\": 55\n
+        \     }\n    ],\n    \"serviceTier\": \"standard\"\n  },\n  \"modelVersion\":
+        \"gemini-2.5-flash-lite\",\n  \"responseId\": \"X_yaapu4PL6t1MkP1Zf1sQI\"\n}\n"
+    headers:
+      Alt-Svc:
+      - h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+      Content-Type:
+      - application/json; charset=UTF-8
+      Date:
+      - Fri, 04 Sep 2026 17:14:08 GMT
+      Server:
+      - scaffolding on HTTPServer2
+      Server-Timing:
+      - gfet4t7; dur=417
+      Transfer-Encoding:
+      - chunked
+      Vary:
+      - Origin
+      - X-Origin
+      - Referer
+      X-Content-Type-Options:
+      - nosniff
+      X-Frame-Options:
+      - SAMEORIGIN
+      X-Gemini-Service-Tier:
+      - standard
+      X-XSS-Protection:
+      - '0'
+      content-length:
+      - '571'
+    status:
+      code: 200
+      message: OK
+version: 1
diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_subagent_transfer_does_not_log_generator_exit.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_subagent_transfer_does_not_log_generator_exit.yaml
new file mode 100644
index 000000000..a53304651
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_subagent_transfer_does_not_log_generator_exit.yaml
@@ -0,0 +1,152 @@
+interactions:
+- request:
+    body: '{"contents": [{"parts": [{"text": "What is the capital of France? Delegate
+      this to the specialist."}], "role": "user"}], "systemInstruction": {"parts":
+      [{"text": "You cannot answer questions yourself. For every request, immediately
+      call transfer_to_agent with agent_name=''capital_specialist''.\n\nYou are an
+      agent. Your internal name is \"coordinator\". The description about you is \"Routes
+      geography questions to the capital specialist without answering them.\".\n\n\nYou
+      have a list of other agents to transfer to:\n\n\nAgent name: capital_specialist\nAgent
+      description: The only agent allowed to answer geography questions.\n\n\nIf you
+      are the best to answer the question according to your description,\nyou can
+      answer it.\n\nIf another agent is better for answering the question according
+      to its\ndescription, call `transfer_to_agent` function to transfer the question
+      to that\nagent. When transferring, do not generate any text other than the function\ncall.\n\n**NOTE**:
+      the only available agents for `transfer_to_agent` function are\n`capital_specialist`.\n"}],
+      "role": "user"}, "tools": [{"functionDeclarations": [{"description": "Transfer
+      the query to another agent.\n\nUse this tool to hand off control to another
+      agent that is more suitable to\nanswer the user''s query according to the agent''s
+      description.\n\nArgs:\n  agent_name: the agent name to transfer to.", "name":
+      "transfer_to_agent", "parameters_json_schema": {"properties": {"agent_name":
+      {"title": "Agent Name", "type": "string", "enum": ["capital_specialist"]}},
+      "required": ["agent_name"], "title": "transfer_to_agentParams", "type": "object"}}]}],
+      "generationConfig": {}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+      x-goog-api-client:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"functionCall\": {\n              \"name\": \"transfer_to_agent\",\n
+        \             \"args\": {\n                \"agent_name\": \"capital_specialist\"\n
+        \             }\n            },\n            \"thoughtSignature\": \"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\"\n
+        \         }\n        ],\n        \"role\": \"model\"\n      },\n      \"finishReason\":
+        \"STOP\",\n      \"index\": 0,\n      \"finishMessage\": \"Model generated
+        function call(s).\"\n    }\n  ],\n  \"usageMetadata\": {\n    \"promptTokenCount\":
+        301,\n    \"candidatesTokenCount\": 22,\n    \"totalTokenCount\": 412,\n    \"promptTokensDetails\":
+        [\n      {\n        \"modality\": \"TEXT\",\n        \"tokenCount\": 301\n
+        \     }\n    ],\n    \"thoughtsTokenCount\": 89,\n    \"serviceTier\": \"standard\"\n
+        \ },\n  \"modelVersion\": \"gemini-2.5-flash\",\n  \"responseId\": \"V_yaasWiJZvv_uMPzazCEQ\"\n}\n"
+    headers:
+      Alt-Svc:
+      - h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+      Content-Type:
+      - application/json; charset=UTF-8
+      Date:
+      - Fri, 04 Sep 2026 17:14:00 GMT
+      Server:
+      - scaffolding on HTTPServer2
+      Server-Timing:
+      - gfet4t7; dur=872
+      Transfer-Encoding:
+      - chunked
+      Vary:
+      - Origin
+      - X-Origin
+      - Referer
+      X-Content-Type-Options:
+      - nosniff
+      X-Frame-Options:
+      - SAMEORIGIN
+      X-Gemini-Service-Tier:
+      - standard
+      X-XSS-Protection:
+      - '0'
+      content-length:
+      - '1482'
+    status:
+      code: 200
+      message: OK
+- request:
+    body: '{"contents": [{"parts": [{"text": "What is the capital of France? Delegate
+      this to the specialist."}], "role": "user"}, {"parts": [{"text": "For context:"},
+      {"text": "[coordinator] called tool `transfer_to_agent` with parameters: {''agent_name'':
+      ''capital_specialist''}"}], "role": "user"}, {"parts": [{"text": "For context:"},
+      {"text": "[coordinator] `transfer_to_agent` tool returned result: {''result'':
+      None}"}], "role": "user"}], "systemInstruction": {"parts": [{"text": "Answer
+      geography questions accurately and in one short sentence.\n\nYou are an agent.
+      Your internal name is \"capital_specialist\". The description about you is \"The
+      only agent allowed to answer geography questions.\".\n\n\nYou have a list of
+      other agents to transfer to:\n\n\nAgent name: coordinator\nAgent description:
+      Routes geography questions to the capital specialist without answering them.\n\n\nIf
+      you are the best to answer the question according to your description,\nyou
+      can answer it.\n\nIf another agent is better for answering the question according
+      to its\ndescription, call `transfer_to_agent` function to transfer the question
+      to that\nagent. When transferring, do not generate any text other than the function\ncall.\n\n**NOTE**:
+      the only available agents for `transfer_to_agent` function are\n`coordinator`.\n\nIf
+      neither you nor the other agents are best for the question, transfer to your
+      parent agent coordinator.\n"}], "role": "user"}, "tools": [{"functionDeclarations":
+      [{"description": "Transfer the query to another agent.\n\nUse this tool to hand
+      off control to another agent that is more suitable to\nanswer the user''s query
+      according to the agent''s description.\n\nArgs:\n  agent_name: the agent name
+      to transfer to.", "name": "transfer_to_agent", "parameters_json_schema": {"properties":
+      {"agent_name": {"title": "Agent Name", "type": "string", "enum": ["coordinator"]}},
+      "required": ["agent_name"], "title": "transfer_to_agentParams", "type": "object"}}]}],
+      "generationConfig": {}}'
+    headers:
+      Content-Type:
+      - application/json
+      user-agent:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+      x-goog-api-client:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.6.3 gl-python/3.14.6
+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"text\": \"The capital of France is Paris.\",\n
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diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_sync_runner_run_does_not_duplicate_invocation_spans.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_sync_runner_run_does_not_duplicate_invocation_spans.yaml
new file mode 100644
index 000000000..429d9b7c9
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_sync_runner_run_does_not_duplicate_invocation_spans.yaml
@@ -0,0 +1,126 @@
+interactions:
+- request:
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diff --git a/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_usage_metadata_metrics.yaml b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_usage_metadata_metrics.yaml
new file mode 100644
index 000000000..18df209cd
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/2.6.3/test_adk_usage_metadata_metrics.yaml
@@ -0,0 +1,135 @@
+interactions:
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diff --git a/py/src/braintrust/integrations/adk/cassettes/latest/test_adk_custom_base_agent_root_preserves_agent_spans.yaml b/py/src/braintrust/integrations/adk/cassettes/latest/test_adk_custom_base_agent_root_preserves_agent_spans.yaml
new file mode 100644
index 000000000..d810a0167
--- /dev/null
+++ b/py/src/braintrust/integrations/adk/cassettes/latest/test_adk_custom_base_agent_root_preserves_agent_spans.yaml
@@ -0,0 +1,62 @@
+interactions:
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+      - application/json
+      user-agent:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.8.0 gl-python/3.14.6
+      x-goog-api-client:
+      - google-genai-sdk/2.22.0 gl-python/3.14.6 google-adk/2.8.0 gl-python/3.14.6
+    method: POST
+    uri: https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-lite:generateContent
+  response:
+    body:
+      string: "{\n  \"candidates\": [\n    {\n      \"content\": {\n        \"parts\":
+        [\n          {\n            \"text\": \"hello\"\n          }\n        ],\n
+        \       \"role\": \"model\"\n      },\n      \"finishReason\": \"STOP\",\n
+        \     \"index\": 0\n    }\n  ],\n  \"usageMetadata\": {\n    \"promptTokenCount\":
+        148,\n    \"candidatesTokenCount\": 1,\n    \"totalTokenCount\": 149,\n    \"promptTokensDetails\":
+        [\n      {\n        \"modality\": \"TEXT\",\n        \"tokenCount\": 148\n
+        \     }\n    ],\n    \"serviceTier\": \"standard\"\n  },\n  \"modelVersion\":
+        \"gemini-2.5-flash-lite\",\n  \"responseId\": \"H_2aaquwJfqt1MkPkraXwQg\"\n}\n"
+    headers:
+      Alt-Svc:
+      - h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+      Content-Type:
+      - application/json; charset=UTF-8
+      Date:
+      - Fri, 04 Sep 2026 17:17:19 GMT
+      Server:
+      - scaffolding on HTTPServer2
+      Server-Timing:
+      - gfet4t7; dur=305
+      Transfer-Encoding:
+      - chunked
+      Vary:
+      - Origin
+      - X-Origin
+      - Referer
+      X-Content-Type-Options:
+      - nosniff
+      X-Frame-Options:
+      - SAMEORIGIN
+      X-Gemini-Service-Tier:
+      - standard
+      X-XSS-Protection:
+      - '0'
+      content-length:
+      - '555'
+    status:
+      code: 200
+      message: OK
+version: 1
diff --git a/py/src/braintrust/integrations/adk/integration.py b/py/src/braintrust/integrations/adk/integration.py
index ce931557f..ca4e5a4f7 100644
--- a/py/src/braintrust/integrations/adk/integration.py
+++ b/py/src/braintrust/integrations/adk/integration.py
@@ -6,7 +6,6 @@
 
 from .patchers import (
     AgentRunAsyncPatcher,
-    AgentRunPatcher,
     FlowRunAsyncPatcher,
     McpToolPatcher,
     RunnerRunPatcher,
@@ -26,7 +25,6 @@ class ADKIntegration(BaseIntegration):
     min_version = "1.14.1"
     patchers = (
         ThreadBridgePatcher,
-        AgentRunPatcher,
         AgentRunAsyncPatcher,
         RunnerRunPatcher,
         FlowRunAsyncPatcher,
diff --git a/py/src/braintrust/integrations/adk/patchers.py b/py/src/braintrust/integrations/adk/patchers.py
index d29b73bf9..69b25a8d7 100644
--- a/py/src/braintrust/integrations/adk/patchers.py
+++ b/py/src/braintrust/integrations/adk/patchers.py
@@ -20,23 +20,13 @@
 # ---------------------------------------------------------------------------
 
 
-class AgentRunPatcher(FunctionWrapperPatcher):
-    """Patch the ADK 2.7+ node entry point used to execute agents."""
-
-    name = "adk.agent.run"
-    target_module = "google.adk.workflow._base_node"
-    target_path = "BaseNode.run"
-    wrapper = _agent_run_async_wrapper
-
-
 class AgentRunAsyncPatcher(FunctionWrapperPatcher):
-    """Patch the legacy ``BaseAgent.run_async`` entry point for tracing."""
+    """Patch the ``BaseAgent.run_async`` agent execution entry point."""
 
     name = "adk.agent.run_async"
     target_module = "google.adk.agents"
     target_path = "BaseAgent.run_async"
     wrapper = _agent_run_async_wrapper
-    superseded_by = (AgentRunPatcher,)
 
 
 # ---------------------------------------------------------------------------
@@ -161,7 +151,6 @@ class McpToolPatcher(FunctionWrapperPatcher):
 
 def wrap_agent(Agent: Any) -> Any:
     """Manually patch an agent class for tracing."""
-    AgentRunPatcher.wrap_target(Agent)
     return AgentRunAsyncPatcher.wrap_target(Agent)
 
 
diff --git a/py/src/braintrust/integrations/adk/test_adk.py b/py/src/braintrust/integrations/adk/test_adk.py
index 84d57955b..e4e699d3c 100644
--- a/py/src/braintrust/integrations/adk/test_adk.py
+++ b/py/src/braintrust/integrations/adk/test_adk.py
@@ -1,4 +1,5 @@
 import os
+from collections.abc import AsyncGenerator
 from importlib.metadata import version as pkg_version
 from pathlib import Path
 
@@ -12,7 +13,9 @@
 
 
 ADK_VERSION = tuple(int(x) for x in pkg_version("google-adk").split(".")[:3])
-from google.adk.agents import LlmAgent, ParallelAgent, SequentialAgent
+from google.adk.agents import BaseAgent, LlmAgent, ParallelAgent, SequentialAgent
+from google.adk.agents.invocation_context import InvocationContext
+from google.adk.events.event import Event
 from google.adk.runners import Runner
 from google.adk.sessions import InMemorySessionService
 from google.adk.tools import google_search
@@ -22,7 +25,9 @@
 
 PROJECT_NAME = "test_adk"
 ADK_MODEL = (
-    "gemini-2.5-flash-lite" if os.environ.get("BRAINTRUST_TEST_PACKAGE_VERSION") == "latest" else "gemini-2.0-flash"
+    "gemini-2.5-flash-lite"
+    if os.environ.get("BRAINTRUST_TEST_PACKAGE_VERSION") in {"latest", "2.6.3"}
+    else "gemini-2.0-flash"
 )
 FIXTURES_DIR = Path(__file__).parent.parent.parent / "fixtures"
 
@@ -231,6 +236,64 @@ def test_adk_sync_runner_run_does_not_duplicate_invocation_spans(memory_logger):
         )
 
 
+@pytest.mark.vcr
+@pytest.mark.asyncio
+async def test_adk_custom_base_agent_root_preserves_agent_spans(memory_logger):
+    """A plain BaseAgent root must preserve agent attribution for its whole subtree."""
+    assert not memory_logger.pop()
+
+    class CustomAgent(BaseAgent):
+        async def _run_async_impl(self, ctx: InvocationContext) -> AsyncGenerator[Event, None]:
+            yield Event(
+                author=self.name,
+                invocation_id=ctx.invocation_id,
+                content=types.Content(role="model", parts=[types.Part(text="step")]),
+            )
+            for sub_agent in self.sub_agents:
+                async for event in sub_agent.run_async(ctx):
+                    yield event
+
+    app_name = "custom_root_app"
+    user_id = "test-user"
+    session_id = "test-session-custom-root"
+    agent = CustomAgent(
+        name="custom_root",
+        sub_agents=[
+            LlmAgent(
+                name="child",
+                model="gemini-2.5-flash-lite",
+                instruction="Reply with only the word hello.",
+            )
+        ],
+    )
+    runner = await _create_runner(agent, app_name=app_name, user_id=user_id, session_id=session_id)
+
+    async for _ in runner.run_async(
+        user_id=user_id,
+        session_id=session_id,
+        new_message=types.Content(role="user", parts=[types.Part(text="Say hello.")]),
+    ):
+        pass
+
+    spans = memory_logger.pop()
+    expected_names = {
+        f"invocation [{app_name}]",
+        "agent_run [custom_root]",
+        "agent_run [child]",
+        "call_llm",
+        "llm_call [direct_response]",
+    }
+    spans_by_name = {span["span_attributes"]["name"]: span for span in spans}
+    assert len(spans) == len(expected_names)
+    assert spans_by_name.keys() == expected_names
+
+    parent_name_by_id = {span["span_id"]: name for name, span in spans_by_name.items()}
+    assert parent_name_by_id[spans_by_name["agent_run [custom_root]"]["span_parents"][0]] == f"invocation [{app_name}]"
+    assert parent_name_by_id[spans_by_name["agent_run [child]"]["span_parents"][0]] == "agent_run [custom_root]"
+    assert parent_name_by_id[spans_by_name["call_llm"]["span_parents"][0]] == "agent_run [child]"
+    assert parent_name_by_id[spans_by_name["llm_call [direct_response]"]["span_parents"][0]] == "call_llm"
+
+
 @pytest.mark.vcr
 @pytest.mark.asyncio
 async def test_adk_braintrust_integration(memory_logger):
diff --git a/py/src/braintrust/integrations/adk/tracing.py b/py/src/braintrust/integrations/adk/tracing.py
index 4d7253598..bf02aa057 100644
--- a/py/src/braintrust/integrations/adk/tracing.py
+++ b/py/src/braintrust/integrations/adk/tracing.py
@@ -352,34 +352,19 @@ def _run_in_context(*target_args: Any, **target_kwargs: Any) -> Any:
 
 
 async def _agent_run_async_wrapper(wrapped: Any, instance: Any, args: Any, kwargs: Any):
-    # ADK 2.7 routes agents and workflows through BaseNode.run. Only add an
-    # agent span for BaseAgent instances; non-agent workflow nodes pass through.
-    from google.adk.agents import BaseAgent
-
-    if not isinstance(instance, BaseAgent):
+    with _start_stream_span(
+        name=f"agent_run [{instance.name}]",
+        type=SpanTypeAttribute.TASK,
+        metadata={"agent_name": instance.name},
+    ) as agent_span:
+        last_event = None
         async with aclosing(wrapped(*args, **kwargs)) as agen:
             async for event in agen:
+                if event.is_final_response():
+                    last_event = event
                 yield event
-        return
-
-    async def _trace():
-        with _start_stream_span(
-            name=f"agent_run [{instance.name}]",
-            type=SpanTypeAttribute.TASK,
-            metadata={"agent_name": instance.name},
-        ) as agent_span:
-            last_event = None
-            async with aclosing(wrapped(*args, **kwargs)) as agen:
-                async for event in agen:
-                    if event.is_final_response():
-                        last_event = event
-                    yield event
-            if last_event:
-                agent_span.log(output=last_event)
-
-    async with aclosing(_trace()) as agen:
-        async for event in agen:
-            yield event
+        if last_event:
+            agent_span.log(output=last_event)
 
 
 async def _flow_run_async_wrapper(wrapped: Any, instance: Any, args: Any, kwargs: Any):
diff --git a/py/src/braintrust/integrations/auto_test_scripts/test_auto_adk.py b/py/src/braintrust/integrations/auto_test_scripts/test_auto_adk.py
index a6abc3f3c..0e0928415 100644
--- a/py/src/braintrust/integrations/auto_test_scripts/test_auto_adk.py
+++ b/py/src/braintrust/integrations/auto_test_scripts/test_auto_adk.py
@@ -6,7 +6,6 @@
 from braintrust.auto import auto_instrument
 from braintrust.integrations.adk.patchers import (
     AgentRunAsyncPatcher,
-    AgentRunPatcher,
     _RunnerRunAsyncSubPatcher,
     _ThreadBridgePlatformSubPatcher,
     _ThreadBridgeRunnersSubPatcher,
@@ -17,7 +16,6 @@
 
 
 platform_thread = importlib.import_module("google.adk.platform.thread")
-base_node = importlib.import_module("google.adk.workflow._base_node") if hasattr(BaseAgent, "run") else None
 assert importlib.import_module("google.adk").__name__ == "google.adk"
 assert pkg_version("google-adk")
 
@@ -27,9 +25,7 @@ def is_patched(target, patcher):
 
 
 # 1. Verify ADK surfaces are not patched initially.
-agent_run_target = base_node.BaseNode.run if base_node is not None else BaseAgent.run_async
-agent_run_patcher = AgentRunPatcher if base_node is not None else AgentRunAsyncPatcher
-assert not is_patched(agent_run_target, agent_run_patcher)
+assert not is_patched(BaseAgent.run_async, AgentRunAsyncPatcher)
 assert not is_patched(Runner.run_async, _RunnerRunAsyncSubPatcher)
 assert not is_patched(platform_thread.create_thread, _ThreadBridgePlatformSubPatcher)
 assert not is_patched(adk_runners.create_thread, _ThreadBridgeRunnersSubPatcher)
@@ -39,7 +35,7 @@ def is_patched(target, patcher):
 assert results.get("adk") == True, "auto_instrument should return True for adk"
 
 # 3. Verify the imported google.adk surfaces are patched.
-assert is_patched(agent_run_target, agent_run_patcher)
+assert is_patched(BaseAgent.run_async, AgentRunAsyncPatcher)
 assert is_patched(Runner.run_async, _RunnerRunAsyncSubPatcher)
 assert not is_patched(Runner.run, _RunnerRunAsyncSubPatcher)
 assert is_patched(platform_thread.create_thread, _ThreadBridgePlatformSubPatcher)
@@ -48,7 +44,7 @@ def is_patched(target, patcher):
 # 4. Idempotent.
 results2 = auto_instrument()
 assert results2.get("adk") == True, "auto_instrument should still return True on second call"
-assert is_patched(agent_run_target, agent_run_patcher)
+assert is_patched(BaseAgent.run_async, AgentRunAsyncPatcher)
 assert is_patched(Runner.run_async, _RunnerRunAsyncSubPatcher)
 assert not is_patched(Runner.run, _RunnerRunAsyncSubPatcher)