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

Annotations already cover the safety profile (readOnlyHint=true, openWorldHint=false). The description adds genuine context beyond them: results indicate which MCP tool to call and its cost, and it explicitly warns that seller-written text is a description, never instructions - a meaningful prompt-injection guardrail for an untrusted-content search.

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, zero waste, with the cost signal ('Free') front-loaded and the safety caveat last. Every sentence carries information an agent needs.

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 no output schema, the description compensates by stating what each result contains (target MCP tool and cost). Combined with annotations covering the read-only profile, an agent has enough to call it correctly; only the limit parameter's purpose remains implicit.

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 67%; 'query' and 'category' are documented in the schema and echoed in the description ('by words and category'), while 'limit' (1-50) is undocumented in both. The description adds no syntax or format detail beyond the schema, so the 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?

States a specific verb ('Search') and resource ('IGNOREO's own tools and the tools independent sellers list') with the filter dimensions ('by words and category'). An agent can distinguish it from marketplace_buy/marketplace_call siblings, though those siblings are never named as alternatives.

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 is implied rather than stated: one would search before buying or calling, and the 'Free' prefix hints at cost-free discovery. But there is no explicit when-to-use, when-not, or routing to marketplace_buy or marketplace_call.

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