registry_tool_badge

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

The annotations already declare readOnlyHint, idempotentHint, non-destructive, and openWorld, and the description does partly repeat that ('Behavior: read-only'). However, 'Public and free' adds real behavioral context not captured by the annotations, telling the agent there is no auth or paywall barrier. It stops short of describing freshness or return shape, which keeps it below a 5.

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?

Purpose and the sibling exclusion are front-loaded in two short sentences, which is efficient. The trailing 'Behavior: read-only.' is largely redundant with the readOnlyHint annotation and slightly dilutes the otherwise tight structure.

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 one-parameter, read-only lookup with no output schema, the description establishes purpose and the key alternative but does not describe what the badge actually returns (score scale, tier, timestamp, or failure behavior for unknown tool ids). An agent knows when to call it but not what to expect back, leaving a meaningful 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?

There is a single required tool_id parameter with 100% schema description coverage, so the schema already carries the parameter meaning. The description implies the identifier refers to one tool but adds no format, lookup, or error semantics beyond the schema. Baseline 3 is appropriate when the schema fully documents the only parameter.

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 first sentence names the resource precisely (a tool's current composite reliability score) and the second clarifies it is a single-tool, free badge. It explicitly excludes the sibling registry_tool_detail by naming what that tool is for, so an agent can separate the two without opening either schema.

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 states the use case directly ('Use when you want one tool's current composite score as a free badge') and names the alternative and the condition that selects it ('Not for the breakdown (use registry_tool_detail)'). This is explicit when/when-not/alternative guidance.

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