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

Annotations already declare readOnly, idempotent, and non-destructive behavior. The description adds genuinely new behavioral details: the response carries a 'provenance' block with per-field origin, verification time, and confidence, and the endpoint is free tier. No contradiction with annotations exists.

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?

The description is two sentences long, front-loaded with the primary purpose, and immediately followed by the key value proposition (provenance, free tier). No filler or redundant restatement of the title exists.

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 single-argument read-only tool with rich annotations, the description is adequate: it states the operation, the identifier mechanism, the provenance response contract, and pricing tier. The absence of an output schema is mitigated by the explicit provenance block and the simple get-profile nature of the tool.

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%, and the slug parameter is thoroughly documented: it is the slug returned by search_funds and should not be guessed. The description itself does not add parameter details beyond the schema, so the baseline of 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?

The description states a specific verb and resource: 'Get the detailed profile of a specific fund by slug.' This clearly identifies the operation and distinguishes it from sibling tools like search_funds (which search) and get_fund_signals (which returns signals). It does not explicitly name the alternatives, but the subject matter makes the purpose clear.

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 slug parameter's schema description explicitly directs callers to 'Call search_funds first rather than guessing' and explains that slugs are not derivable from display names. This gives clear context for when and how to use get_fund, though it does not mention exclusions for all sibling tools.

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