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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed world), but the description adds real behavioral context: it is free, returns readiness signals rather than a licensing decision, and carries explicit linking constraints including refusing commercial links. Some of this is response-style policy rather than tool behavior, which keeps it just below the top score.

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 and trigger conditions are correctly front-loaded, but the second half is a long chain of linking rules and a commercial-link prohibition that reads more like response policy than tool documentation. Useful content, but it dilutes the core definition.

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?

An output schema exists, so return-value detail is not required. Between the description's trigger list, scoping instructions, alternatives, and the 100%-covered parameter, an agent has everything needed to select and invoke this tool 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?

Schema coverage is 100% and the single parameter already documents that authority should be an exact supported name from list_supported_authorities and that omission yields a global check. The description restates the same narrowing/global distinction, adding little syntax or meaning beyond the schema. 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+resource: 'source health and freshness tool' returning 'source/review readiness signals'. It explicitly distinguishes itself from siblings by naming taxi_licence_preflight for one-authority readiness and compare_licensing_requirements for cross-authority comparison.

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?

Gives explicit trigger conditions ('when the user asks whether licensing evidence is current, stale, changed, conflicted, inaccessible, under review, or safe to rely on'), tells how to scope with or without the authority parameter, and routes to two named alternative tools. Nothing is left to inference.

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