Check a background job

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is largely pre-covered; the description nonetheless reinforces this with 'Changes nothing, so it is safe to poll'. It additionally discloses the result-form equivalence ('the full result in the same form the direct tool returns'), which is useful context an agent cannot get from annotations. No auth or rate-limit detail is given.

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?

Three short sentences, each load-bearing: purpose, return behavior, fallback mode, and safety. The most important facts (what it checks, safe to poll) are front-loaded with no filler.

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?

For a single-optional-parameter read tool with an output schema, nothing essential is missing. It covers the create/check relationship, the empty-argument behavior, and the safety profile, and it correctly avoids re-specifying return values at length.

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 coverage is 100% and the single parameter already documents omission behavior, so the baseline is 3. The description adds provenance the schema does not ('an id exactly as start_job returned it') and restates the list-all fallback, giving slightly more than the structured field alone.

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?

Specific verb+resource ('Check a background job') with explicit lineage to the sibling tool that creates the job ('started by start_job'). It also states what is returned (status, then full result) so an agent can distinguish it from start_job or the synchronous tools.

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?

States both operating modes clearly: pass an id to check one job, omit it to enumerate all held jobs. It also notes it is 'safe to poll', which tells the agent when repeated calls are appropriate. It does not explicitly name a when-not-to-use condition or a competing alternative, so it stops short of a 5.

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