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

Annotations already cover read-only and open-world behavior, but the description adds genuinely non-obvious operational context: a $0.002 USDC charge per successful call via x402 on Base/Solana/Arc, with failed calls free. It also discloses that the data comes from public profile pages with coverage limits (no draws, no future bouts), which prevents the agent from over-trusting completeness. It stops short of rate limits or error modes.

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?

Front-loaded with the purpose and covered fields before caveats and pricing; every clause carries information. The pricing sentence is long but is essential decision input, not padding.

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?

With an output schema present, return shape need not be explained, and the description still enumerates the data domains covered. Parameters and safety are covered by schema and annotations, and cost/payment is explicit; only error handling and rate limits remain unstated, which is a minor gap for a read-only fetch.

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' (URL suffix, e.g. 27) and 'fights' (1–50, default 10) are fully documented in the schema. The description only echoes that the id is a Sherdog fighter id and adds no range, default, or behavior detail for the 'fights' parameter, 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 and resource ('Sherdog MMA fighter profile by Sherdog fighter id') and enumerates the returned fields (name, nationality, height, weight, record, fight history), so the agent knows exactly what it retrieves. It does not explicitly contrast itself with siblings like dev_ufcstats or dev_espn_mma, but the Sherdog-specific id anchors it to a distinct source.

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 only implied: 'by Sherdog fighter id' tells the agent which key to supply, and 'no draws or upcoming bouts beyond what the page lists' sets a scope boundary. There is no explicit guidance on when to prefer this over the ESPN/UFC siblings or when not to call it at all.

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