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

No annotations, so the description carries the full burden; it does add real value by disclosing data provenance (cross-checked against ANAB/UKAS/NABCB/etc.) and the caveat that results are not ranked. It omits return shape, pagination behaviour beyond the limit default, and ordering of results, which matter for a 503-item corpus.

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?

Two sentences, front-loaded with the action and the corpus size, followed by the provenance list and the disclaimer. No filler and nothing redundant with the schema.

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?

Covers what is searched and where the data comes from, which is the main ambiguity for a directory tool. With no output schema and no annotations, the description should also say what a result record contains and whether the 503+ set is exhaustively listed, and it does not.

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 80%, so the baseline is 3, but the description adds meaning by naming the accreditation registries that the accreditation_body filter draws from (ANAB, UKAS, PCI SSC, HITRUST, FedRAMP, Cyber AB, CERT-In), helping the agent pick valid filter values. It says nothing about how query interacts with country/framework filters.

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 and resource ('Search ... compliance audit firms') with a clear scope (503+ verified firms). This distinguishes it from get_auditor (single firm) and the search_agents/compare_agents siblings, though it never names those alternatives explicitly.

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 only implied: an agent can infer this is the discovery/listing tool and that get_auditor is the detail lookup, but nothing states when to use this versus those siblings. The 'Not a ranking or endorsement' caveat is useful framing but is not usage guidance.

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