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

Annotations already mark readOnlyHint true, but the description adds valuable context: free and keyless, top 60 ordering, lifetime call counts, and the fact that capability calls are paid. It also specifies the return shape. No contradiction 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 dense but not bloated—three sentences cover purpose, usage, and return format. Every sentence adds value, though it is slightly longer than the minimal viable version.

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 read-only tool with one optional parameter and no output schema, the description fully covers what the tool does, how to use it, what it returns, and the pricing context. No significant gaps.

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 single optional parameter 'category' is fully described in the schema with case-insensitive exact match. The description merely restates 'optionally filtered to one category' without adding new meaning, so baseline 3 applies due to full schema coverage.

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 ('List') and clearly identifies the resource (full MeshMarket catalog), including the kind of data returned (slug, name, kind, category, price, calls) and the optional filter. It also distinguishes this tool as the discovery first-stop, especially with 'Use it FIRST'.

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?

Explicitly instructs to use it first, find a capability, then call the slug as a tool with {input:{...}}, and mentions mesh_signup for a key. However, it does not explicitly state when not to use it or compare it to alternative discovery tools like 'search'.

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