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

Without annotations, the description carries the full burden for behavioral disclosure. It mentions cost and provides an example call, but does not clarify if the tool is read-only, any authentication or rate limits, or the nature of the response. This is adequate but leaves gaps.

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 concise sentences: purpose, use case, example, and cost. Front-loaded and no wasted words. Every sentence adds value.

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 simple one-parameter lookup tool without output schema or annotations, the description covers purpose, usage context, example, and cost. It is mostly complete, though mentioning the return format (e.g., JSON metadata) would further improve completeness.

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?

The schema has no parameter descriptions (0% coverage). The description compensates with a concrete example call showing the parameter format ('symfony/console'), which adds meaning beyond the schema. However, it does not explain that 'pkg' expects a vendor/package format or enumerate possible values.

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 clearly states the tool retrieves Packagist package metadata for PHP-dependency audits. The verb 'Get' and resource 'Packagist package metadata' are specific and distinguish it from sibling lookup tools like lookup_npm or lookup_pypi.

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 explicitly mentions a use case ('PHP-dependency audits'), providing clear context. However, it does not include when not to use it or list alternative tools for other package managers, which could improve guidance.

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