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

Annotations declare readOnlyHint and openWorldHint, covering the safety profile, so the description only needs to enrich. It adds that the payload includes 'recurring opening hours per order channel', which is behavioral/content context beyond the annotations, though it omits auth or rate-limit notes.

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 purpose, followed by the routing hint. No filler or repetition.

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 one-parameter lookup with an output schema (which covers return values) and read-only annotations, the description supplies everything an agent needs: what it returns, the required key, and where to source it.

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 store_number parameter is fully documented in the schema itself ('Pizza Hut's store number, from /pizzahut/stores'). The description's 'by store number' and sibling pointer largely restate the schema, so 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 (Fetch) and resource (one Pizza Hut restaurant) scoped by 'by store number', and identifies the sibling pizzahut_stores as the discovery tool. An agent can distinguish it from pizzahut_stores without opening either schema.

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?

Explicitly routes the agent: 'Use pizzahut_stores to find store numbers', naming the alternative and the condition that selects it (obtaining the store number prerequisite). Nothing is left to inference for a single-parameter lookup.

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