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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so the safety profile is covered. The description adds real value beyond them: the two-stage strategy (careers-page scan, then slug-probing fallback), the scope boundary (no private/Harvest-key data), and that discoveries persist so repeat lookups are instant.

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?

Front-loaded with the core verb+resource in the first clause, and the rest is dense, purposeful detail. The long enumeration of supported ATS providers is the only padding, but it usefully signals coverage breadth.

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?

With no output schema, the description carries the return-value burden and does state what you get (ATS identity plus board token). Persistence behavior is also covered. Only the exact response shape and error/not-found behavior are unspecified, a minor gap.

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 schema descriptions already explain that careers_url is used instead of guessing from domain. The description reinforces the fallback semantics but adds no syntax or precedence detail beyond what the schema states, so baseline 3 applies.

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?

States a specific verb (detect) and resource (the ATS a company uses, plus its board token), and the description's mechanism detail makes it clearly distinct from sibling retrieval tools like ats_jobs and ats_company_jobs. An agent can identify this as the resolver/discovery step without opening any schema.

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?

Usage is implied: use it to figure out which ATS a domain publishes on, supplying either a domain or a careers_url. There is no explicit when-to-use vs ats_company_jobs/ats_jobs routing, nor when-not conditions beyond the private-data scope exclusion. Adequate but leaves the sibling choice to inference.

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