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

With no annotations, the description carries the full burden. It does disclose one real behavioral trait: a genuine search endpoint that returns an explicit no-match rather than an unrelated default list — valuable and non-obvious. But it says nothing about payment/auth (this is an x402 metered tool), pagination, or the shape of a price result, leaving material behavior undisclosed.

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 short sentences, front-loaded with the verb/resource and ending with the routing alternative. No filler and no repetition of the name or title.

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?

No output schema and no annotations exist, so the description must stand in for both; it handles purpose, no-match semantics, and rough return content ('markets with their prices') adequately. The critical gap is the undocumented, internally redundant parameter set, which the description never resolves.

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 description coverage is 0% across 5 string parameters, and the description adds no parameter-level meaning at all. Worse, there are three plausible keyword inputs (q, query, search) plus limit and activeOnly, and nothing tells the agent which one to populate or how limit/activeOnly are expressed as strings.

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?

States a specific verb+resource+scope: 'Search Polymarket by keyword and get the matching markets with their prices.' It also names the sibling it is not (x402-polymarket for tag browsing), so an agent can route between the two search/browse tools without opening a schema.

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?

'Use x402-polymarket to browse by tag instead' gives an explicit alternative with the condition that selects it. It does not, however, distinguish this tool from the many other Polymarket siblings (x402-poly-markets, x402-polymarket-odds, x402-polymarket-scan), so coverage is clear but partial.

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