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

Annotations already declare readOnlyHint=true, and the description adds the exact HTTP method and endpoint (GET /api/v0/prospects/{id}) plus the return envelope { meta, response }, which is valuable because no output schema exists. It omits auth requirements and error behavior, but those are minor for a simple read.

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 short sentences, front-loaded with purpose, then the API endpoint, then the return shape. Every sentence carries non-redundant information and there is no waste.

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 single-item read with 100% schema coverage and a readOnlyHint annotation, the description supplies the missing pieces: the endpoint and the return envelope. Nothing an agent needs to invoke it correctly is missing.

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 description coverage is 100%: both id and fields are fully documented in the schema. The description adds no parameter-level detail beyond the {id} path template, so the schema does the heavy lifting and a baseline 3 is appropriate.

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, and cardinality: 'Fetch a single prospect (sales opportunity).' The domain gloss in parentheses and the explicit 'single' distinguish it from list_prospects and other get_* siblings without needing to open their schemas.

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?

The phrase 'Fetch a single prospect' gives clear context for when to use it (one record by id), but it does not explicitly name when-not to use it or point to list_prospects as the alternative for multiple records. Context is clear, though exclusions are absent.

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