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

Annotations already declare read-only, idempotent, non-destructive behavior. The description adds value by disclosing the response provenance block, the cost/auth model ('free, no API key required'), and the 'THEN' sequencing. No contradiction with 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 short sentences with clear labels (THEN, COST) and a direct, actionable warning. Every sentence earns its place; there is no filler or redundant rephrasing of the schema.

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-parameter read-only tool with no output schema, the description covers the input precondition, the response provenance behavior, and the common failure mode. It stops short of enumerating the profile fields, but that is not essential for an agent to 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 description coverage is 100%, and the schema already explains the slug requirement and the warning not to guess it. The description repeats this same guidance but does not add any new parameter-level meaning beyond what the schema provides, so 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?

The description opens with a specific verb-resource pair: 'get the detailed profile of one fund.' It also specifies the required input source ('using a slug returned by search_funds'), which distinguishes this detail-lookup from the sibling search and signal tools, even without naming them.

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 gives clear, actionable usage guidance: call search_funds first, never guess the slug from the display name, and explains the consequence ('the call is wasted'). It does not explicitly contrast with get_fund_signals or get_gp_profile, so it falls short of the full when/when-not-alternatives bar.

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