check_compatibility

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

Annotations already declare read-only, open-world, and idempotent behavior. The description adds the return structure ({compatible, conflicts[], notes}), which helps the agent understand what to expect. No contradictions with annotations.

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?

The description is very concise, using a question format for purpose, a clear USE WHEN section with examples, and a RETURNS specification. Every sentence provides useful information without redundancy.

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?

The description gives a clear purpose, usage scenarios, and return shape, which is sufficient for a simple tool with good annotations and a clear schema. It could be slightly more detailed about the contents of 'conflicts[]', but overall it's complete enough for an agent to select and invoke correctly.

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 input schema already describes the 'packages' parameter with an example (100% coverage). The description provides an additional example in the use-case context, but doesn't add significant semantic meaning beyond the schema. 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?

The description clearly states the tool's function: checking if a specific multi-package version combo is verified to work together, with a concrete example (next@15 + react@19 + node@22). It also distinguishes from sibling tools like check_package and check_bulk by focusing on multi-package version compatibility.

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 provides explicit USE WHEN scenarios: pinning a stack and before recommending a version matrix. However, it doesn't explicitly mention alternatives or when not to use the tool, so it falls short of a perfect score.

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