get_build_failure_logs

Retrieve failure logs from CircleCI builds to identify and debug issues causing pipeline failures.

Instructions

This tool helps debug CircleCI build failures by retrieving failure logs.

CRITICAL REQUIREMENTS:
1. Truncation Handling (HIGHEST PRIORITY):
   - ALWAYS check for <MCPTruncationWarning> in the output
   - When present, you MUST start your response with:
     "WARNING: The logs have been truncated. Only showing the most recent entries. Earlier build failures may not be visible."
   - Only proceed with log analysis after acknowledging the truncation

Input options (EXACTLY ONE of these THREE options must be used):

Option 1 - Project Slug and branch (BOTH required):
- projectSlug: The project slug obtained from listFollowedProjects tool (e.g., "gh/organization/project")
- branch: The name of the branch (required when using projectSlug)

Option 2 - Direct URL (provide ONE of these):
- projectURL: The URL of the CircleCI project in any of these formats:
  * Project URL: https://app.circleci.com/pipelines/gh/organization/project
  * Pipeline URL: https://app.circleci.com/pipelines/gh/organization/project/123
  * Legacy Job URL: https://circleci.com/pipelines/gh/organization/project/123
  * Workflow URL: https://app.circleci.com/pipelines/gh/organization/project/123/workflows/abc-def
  * Job URL: https://app.circleci.com/pipelines/gh/organization/project/123/workflows/abc-def/jobs/xyz

Option 3 - Project Detection (ALL of these must be provided together):
- workspaceRoot: The absolute path to the workspace root
- gitRemoteURL: The URL of the git remote repository
- branch: The name of the current branch

Recommended Workflow:
1. Use listFollowedProjects tool to get a list of projects
2. Extract the projectSlug from the chosen project (format: "gh/organization/project")
3. Use that projectSlug with a branch name for this tool

Additional Requirements:
- Never call this tool with incomplete parameters
- If using Option 1, make sure to extract the projectSlug exactly as provided by listFollowedProjects
- If using Option 2, the URLs MUST be provided by the user - do not attempt to construct or guess URLs
- If using Option 3, ALL THREE parameters (workspaceRoot, gitRemoteURL, branch) must be provided
- If none of the options can be fully satisfied, ask the user for the missing information before making the tool call

Input Schema

TableJSON Schema

Name	Required	Description	Default
`params`	No

Implementation Reference

src/tools/getBuildFailureLogs/handler.ts:13-69 (handler)

The main handler function that implements the get_build_failure_logs tool logic, extracting project details and fetching/formatting CircleCI pipeline job logs.

export const getBuildFailureLogs: ToolCallback<{
  params: typeof getBuildFailureOutputInputSchema;
}> = async (args) => {
  const {
    workspaceRoot,
    gitRemoteURL,
    branch,
    projectURL,
    projectSlug: inputProjectSlug,
  } = args.params;

  let projectSlug: string | undefined;
  let pipelineNumber: number | undefined;
  let branchFromURL: string | undefined;
  let jobNumber: number | undefined;

  if (inputProjectSlug) {
    if (!branch) {
      return mcpErrorOutput(
        'Branch not provided. When using projectSlug, a branch must also be specified.',
      );
    }
    projectSlug = inputProjectSlug;
  } else if (projectURL) {
    projectSlug = getProjectSlugFromURL(projectURL);
    pipelineNumber = getPipelineNumberFromURL(projectURL);
    branchFromURL = getBranchFromURL(projectURL);
    jobNumber = getJobNumberFromURL(projectURL);
  } else if (workspaceRoot && gitRemoteURL && branch) {
    projectSlug = await identifyProjectSlug({
      gitRemoteURL,
    });
  } else {
    return mcpErrorOutput(
      'Missing required inputs. Please provide either: 1) projectSlug with branch, 2) projectURL, or 3) workspaceRoot with gitRemoteURL and branch.',
    );
  }

  if (!projectSlug) {
    return mcpErrorOutput(`
          Project not found. Ask the user to provide the inputs user can provide based on the tool description.

          Project slug: ${projectSlug}
          Git remote URL: ${gitRemoteURL}
          Branch: ${branch}
          `);
  }

  const logs = await getPipelineJobLogs({
    projectSlug,
    branch: branchFromURL || branch,
    pipelineNumber,
    jobNumber,
  });

  return formatJobLogs(logs);
};

src/tools/getBuildFailureLogs/inputSchema.ts:7-35 (schema)

Zod input schema defining parameters for the tool: projectSlug, branch, projectURL, workspaceRoot, gitRemoteURL.

export const getBuildFailureOutputInputSchema = z.object({
  projectSlug: z.string().describe(projectSlugDescription).optional(),
  branch: z.string().describe(branchDescription).optional(),
  projectURL: z
    .string()
    .describe(
      'The URL of the CircleCI project. Can be any of these formats:\n' +
        '- Project URL with branch: https://app.circleci.com/pipelines/gh/organization/project?branch=feature-branch\n' +
        '- Pipeline URL: https://app.circleci.com/pipelines/gh/organization/project/123\n' +
        '- Workflow URL: https://app.circleci.com/pipelines/gh/organization/project/123/workflows/abc-def\n' +
        '- Job URL: https://app.circleci.com/pipelines/gh/organization/project/123/workflows/abc-def/jobs/xyz',
    )
    .optional(),
  workspaceRoot: z
    .string()
    .describe(
      'The absolute path to the root directory of your project workspace. ' +
        'This should be the top-level folder containing your source code, configuration files, and dependencies. ' +
        'For example: "/home/user/my-project" or "C:\\Users\\user\\my-project"',
    )
    .optional(),
  gitRemoteURL: z
    .string()
    .describe(
      'The URL of the remote git repository. This should be the URL of the repository that you cloned to your local workspace. ' +
        'For example: "https://github.com/user/my-project.git"',
    )
    .optional(),
});

src/tools/getBuildFailureLogs/tool.ts:4-46 (registration)

Tool object registration defining the name 'get_build_failure_logs', detailed description, and references the input schema.

export const getBuildFailureLogsTool = {
  name: 'get_build_failure_logs' as const,
  description: `
    This tool helps debug CircleCI build failures by retrieving failure logs.

    CRITICAL REQUIREMENTS:
    1. Truncation Handling (HIGHEST PRIORITY):
       - ALWAYS check for <MCPTruncationWarning> in the output
       - When present, you MUST start your response with:
         "WARNING: The logs have been truncated. Only showing the most recent entries. Earlier build failures may not be visible."
       - Only proceed with log analysis after acknowledging the truncation

    Input options (EXACTLY ONE of these THREE options must be used):

    ${option1DescriptionBranchRequired}

    Option 2 - Direct URL (provide ONE of these):
    - projectURL: The URL of the CircleCI project in any of these formats:
      * Project URL: https://app.circleci.com/pipelines/gh/organization/project
      * Pipeline URL: https://app.circleci.com/pipelines/gh/organization/project/123
      * Legacy Job URL: https://circleci.com/pipelines/gh/organization/project/123
      * Workflow URL: https://app.circleci.com/pipelines/gh/organization/project/123/workflows/abc-def
      * Job URL: https://app.circleci.com/pipelines/gh/organization/project/123/workflows/abc-def/jobs/xyz

    Option 3 - Project Detection (ALL of these must be provided together):
    - workspaceRoot: The absolute path to the workspace root
    - gitRemoteURL: The URL of the git remote repository
    - branch: The name of the current branch
    
    Recommended Workflow:
    1. Use listFollowedProjects tool to get a list of projects
    2. Extract the projectSlug from the chosen project (format: "gh/organization/project")
    3. Use that projectSlug with a branch name for this tool

    Additional Requirements:
    - Never call this tool with incomplete parameters
    - If using Option 1, make sure to extract the projectSlug exactly as provided by listFollowedProjects
    - If using Option 2, the URLs MUST be provided by the user - do not attempt to construct or guess URLs
    - If using Option 3, ALL THREE parameters (workspaceRoot, gitRemoteURL, branch) must be provided
    - If none of the options can be fully satisfied, ask the user for the missing information before making the tool call
    `,
  inputSchema: getBuildFailureOutputInputSchema,
};

src/circleci-tools.ts:30-44 (registration)

Registration of the tool in the main CCI_TOOLS array export.

export const CCI_TOOLS = [
  getBuildFailureLogsTool,
  getFlakyTestLogsTool,
  getLatestPipelineStatusTool,
  getJobTestResultsTool,
  configHelperTool,
  createPromptTemplateTool,
  recommendPromptTemplateTestsTool,
  runPipelineTool,
  listFollowedProjectsTool,
  runEvaluationTestsTool,
  rerunWorkflowTool,
  analyzeDiffTool,
  runRollbackPipelineTool,
];

src/circleci-tools.ts:58-72 (registration)

Mapping of the tool name to its handler function in the CCI_HANDLERS object.

export const CCI_HANDLERS = {
  get_build_failure_logs: getBuildFailureLogs,
  find_flaky_tests: getFlakyTestLogs,
  get_latest_pipeline_status: getLatestPipelineStatus,
  get_job_test_results: getJobTestResults,
  config_helper: configHelper,
  create_prompt_template: createPromptTemplate,
  recommend_prompt_template_tests: recommendPromptTemplateTests,
  run_pipeline: runPipeline,
  list_followed_projects: listFollowedProjects,
  run_evaluation_tests: runEvaluationTests,
  rerun_workflow: rerunWorkflow,
  analyze_diff: analyzeDiff,
  run_rollback_pipeline: runRollbackPipeline,
} satisfies ToolHandlers;

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