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

Annotations already declare read-only, idempotent, non-destructive. The description adds valuable behavioral context: 'never returns contact details beyond the public links' and explains the storefront URL is the contact path, a privacy boundary not visible in the 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?

Three tightly packed sentences: the first lists the contents, the second gives usage guidance, and the third states a key limitation. No filler or redundant content.

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?

For a simple get-by-id profile tool with only two parameters and no output schema, the description fully covers what is returned, when to use it, and a critical limitation. It is complete enough for an agent to invoke and interpret results 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%, providing baseline 3 credit. The description adds slight extra meaning by clarifying the vendor_id can refer to 'one vendor or venue' and reinforcing that the id comes from search_vendors, though this largely duplicates the schema's own description.

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 clearly states the tool returns the full public storefront of one vendor or venue by id, listing specific content fields like categories, price band, capacity, packages, FAQ, and reviews. It also distinguishes itself from search_vendors by explicitly sourcing the id from that search tool.

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?

It says to 'Use it after a search to answer detailed questions or to compare shortlisted vendors,' giving explicit when-to-use context. It also warns that contact details are never returned and points to the storefront URL for contact, but it does not explicitly name other sibling tools as alternatives for related tasks.

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