analyze-github-flake

Expertise in analyzing flake github issues in the flutter/flutter repository. Use when a user wants to analyze the flakiness of a specific link to a flutter…

npx skills add https://github.com/flutter/flutter --skill analyze-github-flake

Flake analysis instructions

Rules You should not modify ANY files - you are only to provide an analysis of why the specific check is flaking. You should only look at the issue body, as well as comments containing links to additional builds. You should not attempt to solve the flakes or pinpoint root causes inside of flutter/, just provide a high level summary of what is going on and bucket the failures into distinct types.

Collecting the list of failing builds and obtaining the logs

Github issue urls take the form of https://github.com/flutter/flutter/issues/. Where issue-number is a number.

Get information about the issue by using gh issue view <issue-number> --repo flutter/flutter --json=author,body,id,labels,number,state,title,url

For example to find information about the issue https://github.com/flutter/flutter/issues/174116 you can call gh issue view 174116 --repo flutter/flutter --json=author,body,id,labels,number,state,title,url

At this point there are two possible cases. If the issue

  1. Is filed by fluttergithubbot
  2. Has a title of the format "<ci.yaml target> is X% flaky" Then it is of the type we are looking to analyze. If it is not, you should short circuit here, either notifying the user that the issue is not filed by the github flake bot (if they directly asked for the skill to be invoked) or otherwise continue with your previous work (if they did not).

If the previous conditions are met, the title will contain the name of the flaking check, and the body will contain urls which link to instances where the check failed or flaked, each on a new line, directly after "Flaky builds:". You should also inspect the comments and find each comment made by "login": "fluttergithubbot", and extract the urls from there as well (the format will be the same, with an example flake at the top, and the full list immediately after the "Flaky builds:" header).

To find information about the specific failure take one of the urls listed in the issue body. That link takes the format "https://ci.chromium.org/ui/p/flutter/builders/<bucket>/<check_name>/<buildNumber>/overview",

Example https://ci.chromium.org/ui/p/flutter/builders/prod/Windows%20plugin_test/16247/overview where prod is the , Windows%20plugin_test is the <check_name> and 16247 is the .

Then use the to get the test logs metadata by running the following command.

curl 'https://cr-buildbucket.appspot.com/prpc/buildbucket.v2.Builds/GetBuild' \
  -H 'accept: application/json' \
  -H 'accept-language: en-US,en;q=0.9,es;q=0.8' \
  -H 'cache-control: no-cache' \
  -H 'content-type: application/json' \
  -H 'origin: https://ci.chromium.org' \
  -H 'pragma: no-cache' \
  -H 'priority: u=1, i' \
  -H 'referer: https://ci.chromium.org/' \
  -H 'sec-ch-ua: "Chromium";v="146", "Not-A.Brand";v="24", "Google Chrome";v="146"' \
  -H 'sec-ch-ua-mobile: ?0' \
  -H 'sec-ch-ua-platform: "macOS"' \
  -H 'sec-fetch-dest: empty' \
  -H 'sec-fetch-mode: cors' \
  -H 'sec-fetch-site: cross-site' \
  -H 'user-agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/146.0.0.0 Safari/537.36' \
  -H 'x-return-encrypted-headers: all' \
  --data-raw '{"builder":{"project":"flutter","bucket":"<bucket>","builder":"<check_name>"},"buildNumber":<buildNumber>,"mask":{"fields":"id,builder,builderInfo,number,canceledBy,createdBy,createTime,startTime,endTime,cancelTime,status,statusDetails,summaryMarkdown,output,steps,tags,schedulingTimeout,executionTimeout,gracePeriod,ancestorIds,retriable"}}'

Ignore the characters )]}' that start the response and treat the rest like json.

Inspect the content of the logs to determine the cause of the failure.

Do this for each of the urls in the issue body. Collect the logs for each of the specific failures, and categorize them by the type of failure in to a high level summary.

More skills from flutter

dart-modern-features
flutter
To find candidates for modernization:
flutter-fix-layout-issues
flutter
Fixes Flutter layout errors (overflows, unbounded constraints) using Dart and Flutter MCP tools. Use when addressing "RenderFlex overflowed", "Vertical…
adding-release-notes
flutter
Adds user-facing change descriptions to DevTools release notes. Use when documenting improvements, fixes, or new features in the NEXT_RELEASE_NOTES.md file.
reviewing-devtools-prs
flutter
DevTools repository-specific PR review workflow enforcing DevTools style guidelines and common review patterns. Use when reviewing pull requests in the…
dart-use-primary-constructors
flutter
Help users write syntactically and semantically correct primary constructors in Dart, and migrate/use the new constructor syntax, empty-body semicolon syntax,…
code-documentation
flutter
Guide for writing effective code documentation, including docstrings, JSDoc, dartdoc, and implementation comments. Use this skill when writing new code, adding…
api-review
flutter
Reviews the specified code against the canonical API Design guidelines. Use this skill when the user asks for an API review or to check code against API design…
flutter-accessibility
flutter
Implement WCAG 2 and EN 301 549 accessibility standards and adaptive layouts in Flutter apps. Enforces semantic annotations, tap target sizes (48x48 dp minimum), and text contrast ratios (4.5:1 for small text, 3:1 for large) across mobile, web, and desktop platforms Provides decision logic for web semantics initialization, interactive widget wrapping, screen-size-based layout switching, and keyboard/mouse input handling Includes focus traversal management via FocusTraversalGroup and...