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

Annotations already declare readOnly, idempotent, non-destructive behavior, so the description focuses on value beyond that. It adds two genuinely important behavioral facts: the response is the *public* view, and additional fields (website, email, phone, people, timeline, technology) are gated behind FirmLedger Pro — a tier/authorization constraint an agent cannot infer from annotations.

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?

Purpose is front-loaded, but the body is a single sprawling sentence with a long comma-laden enumeration and a fuzzy trailing metaphor ('the same line the website draws') that adds ambiguity rather than information. It is dense rather than wasteful, but the structure could be broken up profitably.

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 and a closed-world, read-only single-record tool, the description carries the burden of telling the agent what comes back, and it does so thoroughly, including the Pro-gated section and the revenue-history semantics. Minor gaps remain: no note on behavior when no company matches the identifier, and no hint that the ten-year answer may be incomplete beyond the phrase 'explicit gaps'.

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 'listing' parameter description already documents all four accepted identifier forms with a recommended one. The description adds nothing about the parameter itself, so the 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?

The description names a specific resource and cardinality: 'The public FirmLedger profile of one company', then enumerates the contents (verification state, scores, revenue history, jobs count, news). The implied retrieve-single-record verb and 'one company' scope distinguish it from search_listings, but the differentiation is never stated 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?

There is no explicit when-to-use or when-not-to-use guidance, and no alternatives are named (compare_listings, get_lead, refresh_listing_* siblings are never mentioned). Usage is only implied by the fact that it fetches detail for a single company, and the useful hint that slugs come from search_listings lives in the schema, not the description.

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