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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description only needs to add context — which it does by disclosing a per-call billing/quota cost that no annotation conveys. It doesn't discuss failure behavior (e.g., unknown id), keeping it short of a 5.

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?

One sentence, front-loaded with the action and resource, then a precise field inventory, then the cost caveat. No filler and nothing that could be cut without losing information.

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?

Output schema exists, so return details are already covered, and rich annotations cover the safety profile; the description contributes an endpoint reference, payload summary, and quota cost. Only missing piece is error/not-found behavior, a minor gap for a simple single-id lookup.

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 the single parameter already documents its origin ('A company id from search_companies'). The description adds nothing about the id beyond 'by id', so this is the baseline 3 where the schema carries all parameter meaning.

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+resource ('One employer's profile by id') and even names the underlying endpoint. The parenthetical enumerates exactly what the payload contains (what it does, industry, size, founding year, HQ, social links), so an agent can distinguish it from list-style siblings like search_companies at a glance.

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?

The phrase 'by id' plus the schema note that the id comes from search_companies implies a detail-lookup-after-search workflow, but the description itself never states when to use this versus search_companies or get_job. The only explicit guidance is the cost signal ('Counts as one toward the monthly allowance'), which is useful but not use-case routing.

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