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

Annotations already declare it read-only, idempotent, non-destructive and open-world, so the safety profile is covered; the description still adds real behavioral context by listing supported sources (Greenhouse, Lever, SmartRecruiters, Ashby, most career pages) and hard coverage boundaries (LinkedIn/Indeed/Glassdoor fail). This is exactly the kind of beyond-annotation disclosure that helps an agent predict outcomes.

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 front-loaded with purpose then scope, and the return-field list and exclusion list both earn their place. It is a touch long and list-heavy, but there is no filler sentence to cut.

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?

There is no output schema, so the description must convey return shape, and it does so by enumerating the extracted fields. Combined with supported/unsupported sources and the fallback path, an agent has everything needed to decide and 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?

There is a single required parameter with 100% schema description coverage ('The full link to the job advert'), so the schema already carries the semantics. The description implies the URL must be a job advert link but adds no format, host, or validation detail beyond that, which is the expected baseline when the schema does the work.

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 names a specific verb and resource ('Check a job link', 'Reads the advert from the employer's job board') and enumerates exactly what it returns (title, company, place, pay, posted date, liveness, visa sponsorship, summary). It is clearly distinguishable from siblings like match_cv, which it explicitly redirects to for non-scrapable pages.

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 gives concrete trigger phrasings ('is this job real?', 'what does this one pay?') that map to the tool, and states when NOT to use it: LinkedIn, Indeed and Glassdoor pages can't be read, with the fallback (paste advert text into the CV match) named explicitly.

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