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

Annotations already declare a safe read (readOnlyHint=true, openWorldHint=false), so the bar is lower, and the description still adds meaningful behavior: mainnet-only scoping, a privacy guarantee about withholding holder identity, and an explicit prompt-injection warning that names/descriptions are third-party data. That content-warning is exactly the kind of context annotations cannot convey.

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, each doing distinct work: what is returned, a scope restriction, and a safety warning. The contents are front-loaded and there is no filler or repetition.

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 two-parameter read-only tool with no output schema, the description covers what is returned, the network scope, and an important trust caveat. Only the exact shape of the returned record and any error/not-found behavior remain unstated, which is a minor gap.

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 both parameters are documented inline (key e.g. first-win, gameId as gm_…). The description adds no further meaning about their format or relationship, so the baseline 3 is correct.

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 names the specific resource (a badge's public record) and enumerates its contents: game, player count, on-chain collection, and explicitly excludes holder identity. That exclusion helps separate it from siblings like my_badge_player or verify_soulbound_holder. The retrieval verb is only implicit ('A badge's public record'), which keeps it just short of a 5.

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?

'Mainnet badges only' is a real usage constraint, and 'never who holds it' hints that holder lookups belong to another tool. But no sibling is named and there is no explicit when-to-use statement, so the routing signal is implied rather than stated.

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