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

Annotations (readOnlyHint=true, idempotentHint=true, destructiveHint=false) already carry the safety profile, so the bar is lower. The description adds value by disclosing output traits beyond the schema: the response is plain-text and contains no employer apply URL. This level of added context exceeds baseline for an annotated read-only tool.

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?

Four short sentences with zero waste. The usage context is front-loaded, the search prohibition is explicit, and the output traits are stated in two punchy fragments. Every sentence earns its place.

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 simple two-parameter, read-only, idempotent tool, nothing critical is missing. The description covers invocation source, parameter choice, the search exclusion, and the key output characteristics (plain-text, no employer apply URL) — the latter being important since no output schema exists to document return values.

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%, so the baseline of 3 applies. The description reinforces the schema ('Pass that job's url from search_jobs or hiring_now (or its slug)') and mirrors the preference hierarchy (url preferred, slug fallback), but it adds no new semantic information beyond what the schema already documents.

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 implies the purpose — fetch a specific job's details after a search — via usage context ('Use after search_jobs or hiring_now when the user picked one job') rather than a crisp verb+resource statement. It does differentiate from siblings with 'Do not use this to search,' and the output hints ('Plain-text description. No employer apply URL') clarify what the agent gets back, but the core function is left to inference.

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?

Explicitly states when to use ('after search_jobs or hiring_now when the user picked one job'), what input to pass (that job's url or slug), and the exclusion ('Do not use this to search'). This is textbook routing guidance that distinguishes the tool from its siblings without ambiguity.

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