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

Annotations already declare readOnlyHint/openWorldHint/non-idempotent, so the safety profile is covered. The description goes beyond that by disclosing the analytical behavior (conflicts explained, end-of-life runtimes flagged), the 20-package cap, and the pricing model ($0.005 USDC via x402 or prepaid, free trial) – genuinely useful context for invocation decisions.

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 dense paragraph that front-loads the core question and capability before tacking pricing onto the end. No wasted sentences, though the clause about engines/peer deps is fairly packed.

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?

With an output schema present, return values need not be explained. The description covers inputs, limits, ecosystems, pricing and behavior adequately; the only gap is the absence of any routing against the numerous sibling compatibility/audit tools.

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%, so the baseline is 3. The description does add the 20-package limit and the accepted version format ('exact versions, ranges or latest'), but these largely restate the schema's own maxItems and examples, so value beyond structured fields is marginal.

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 leads with a specific question ('Do these package versions work together and on your runtime?') and names the exact mechanism – engines, peer dependencies, Requires-Python/Requires-Dist checked against each other and the runtime. It's concrete about verb and resource, though it doesn't name a sibling (e.g. package-check, dependency-verdict) to distinguish itself.

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?

Usage context is implied through the input shape ('Give up to 20 npm or PyPI packages... plus your Node or Python version'), which tells the agent what to supply, but there is no explicit when-to-use-this-vs-alternatives guidance despite many overlapping siblings (package-check, package-audit, dependency-report).

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