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

Beyond annotations (readOnlyHint, openWorldHint), the description discloses critical behavioral details: premium residential proxy, specific pricing ($0.005 USDC per successful call via x402 on Base/Solana/Arc), failed calls not charged, and that subscriber-only performance data is excluded. This adds substantial transparency for cost and data availability.

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 front-loaded with the returned data fields, followed by input format, proxy/limitation notes, and pricing. Every sentence serves a purpose and there is no redundant or filler text.

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?

Given the simple schema (one parameter), the presence of an output schema, and the annotations covering safety and openness, the description provides all needed context: data scope, input format, proxy behavior, data exclusions, and cost model. Nothing essential 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%, and the schema already documents the single 'id' parameter with an example. The description repeats the ID format and URL pattern, adding little new meaning beyond the schema, 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 specifies the resource (PitchBook public fund profile) and enumerates the data fields returned, making the tool's purpose clear. However, it lacks a direct verb (e.g., 'fetch') and does not explicitly differentiate from sibling tools like finance_pitchbook_investors, though the name implies fund data.

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?

Usage is implied by the data scope and the input format (fund id from URL), and a limitation is noted ('subscriber-only performance data is not included'). But there is no explicit guidance on when to use this tool versus alternatives, nor any exclusions beyond the subscriber data note.

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