Check job status (free)

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

Annotations already declare readOnlyHint=true, so the bar is lower, but the description still adds substantial context: return fields, the nuanced meaning of result_ok, cross-release incompatibility, and the growing poll_after_ms backoff. It also explicitly notes the tool is free and performs no model call. No contradiction with annotations.

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

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

The description is longer than a minimal two-sentence snippet, but it is well-structured with front-loaded purpose, then grouped paragraphs for result semantics and polling behavior. Every sentence contributes unique, non-redundant detail, though a slightly more condensed version could improve scannability.

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

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

Given the tool's complexity, the description is complete: it covers when to use, what fields are returned, the semantics of result_ok, cross-release pitfalls, and retention behavior. An output schema exists, so return-value details are not required. The description leaves no critical gap for an agent to invoke and interpret the call correctly.

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

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

Schema description coverage is 100%, and both parameters (job_id and workspace_root) have thorough descriptions in the schema itself. The tool description adds no additional parameter-level semantics beyond the schema's coverage, so it stays at the baseline of 3.

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

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

The description opens with a specific verb and resource: 'Check a background job's lifecycle state without fetching the full result.' It clearly distinguishes itself from siblings like codex_job_result (which fetches the result) and from the async/sync job-launching tools. This is a textbook example of purpose clarity.

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

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

It explicitly states when to use the tool: 'Use after any *_async call ... or any sync consult/review/delegate (whose meta.job_id names its record).' It also gives forward guidance: 'when it is true, call codex_job_result,' and provides operational guidance on polling ('Honor poll_after_ms between polls'). This covers both timing and relationship to alternatives with actionability.

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