cicd-aiops

job_trace_tail

Read-only

Fetch the trailing lines of a CI/CD job's log/trace by project and job to diagnose failures; increase tail_lines if truncation hides earlier errors.

Instructions

[READ] The tail of one job's log/trace — where the failure explains itself.

Returns {project, job, trace, totalLines, tailLines, returned, limit, truncated, charsTruncated}. 'truncated' true means earlier lines were dropped (the trace is only the tail — the FIRST error may be above the window, so raise tail_lines before concluding a root cause); 'charsTruncated' true means the tail itself hit the byte ceiling.

Args: project: Project id or full path. job: Job id (from pipeline_jobs). tail_lines: How many trailing lines to return (default 60). target: Server target name from config; omit for the default.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "project": "<project>",
      "job": "<job>"
    },
    "name": "job_trace_tail"
  }
}

Input Schema

Name	Required	Description	Default
`job`	Yes
`target`	No
`project`	Yes
`tail_lines`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.5.0Jul 25, 2026

TDQS

A4.4/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With only readOnlyHint provided, the description carries the behavioral load and does so well: it details the returned fields, explains that 'truncated' means earlier lines were dropped (so the first error may be above the window), and warns about 'charsTruncated' hitting a byte ceiling. This is rich disclosure beyond the annotation.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with a [READ] tag and one-line purpose, then return shape, then truncation caveats, then Args. The return-field enumeration is dense but justified given no output schema; overall each block earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given no output schema, the description covers purpose, all params, and the truncation semantics that govern correct interpretation. It omits error behavior (e.g., unknown job/project) but is otherwise sufficient to call and interpret the tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0%, so the description must compensate, and it documents all four params: project (id or full path), job (id from pipeline_jobs), tail_lines (trailing line count/default 60), and target (server target name, omit for default). Each adds meaning beyond the bare schema types.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource — 'the tail of one job's log/trace' — and frames its use case ('where the failure explains itself'). It distinguishes itself by noting the job id comes 'from pipeline_jobs', but does not explicitly contrast with sibling RCA tools like pipeline_failure_rca.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives clear situational context (diagnosing job failures) and even an actionable rule: 'raise tail_lines before concluding a root cause' if truncated. However, it names no alternative tool or when-not-to-use condition, so the agent must infer routing.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.