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

Without annotations, the description carries the full burden. It mentions what is returned (score, grade, findings, certification status) and implies a read-only operation, but does not explicitly state it is non-destructive or idempotent. Additional behavioral details like rate limits or authentication needs are absent.

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?

A single informative sentence with no wasted words. The description is front-loaded with the core action 'Look up the trust score' and quickly specifies the resources and return values.

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 lack of annotations and output schema, the description provides a reasonable overview of what the tool does and returns. It covers the two lookup methods and the key return fields, making it mostly complete for a simple lookup tool. Minor gaps like explanation of 'trust score' are acceptable.

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 coverage is 100% with both parameters described. The description adds value by clarifying that either a URL or npm package name can be used, which is not explicitly stated in the schema. This helps the agent understand mutual exclusivity, though not stating it as required.

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 uses a specific verb 'look up' and resource 'trust score', clearly identifying the tool's function. It distinguishes from sibling tools like scan_server or search_registry which perform different operations.

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?

The description clearly indicates the tool is for looking up trust scores by URL or npm package name, providing clear context. However, it does not explicitly state when not to use it or suggest alternative tools for different scenarios.

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