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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds value by clarifying that results are informational articles, not referral links, and that search works in any language. It doesn't contradict annotations. It could add more about pagination or result ordering, but the core behavioral traits are disclosed.

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 two sentences with no wasted words. It front-loads the core function (searches by keyword), then adds the return format and the key differentiator (not referral links). Every sentence earns its place.

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 tool has an output schema, so return values are documented elsewhere. The description covers the search scope, language support, and the informational nature of results. It doesn't mention pagination or result ordering, but for a simple search tool with an output schema and strong annotations, this is adequate. The only minor gap is not explaining the 'limit' parameter's effect, but the schema covers that.

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%, so the description carries the burden for parameter semantics. The description mentions keyword search and any language, which maps to the 'query' and 'lang' parameters, but it doesn't explain the 'limit' parameter or provide details on how language filtering works. The schema itself defines the parameters with types, defaults, and constraints, so the description adds some context but doesn't fully compensate for the 0% 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 clearly states the tool's function: searching CoinRebate's published guides by keyword and returning matching articles with title, one-line description, and URL. It also distinguishes itself from referral-link tools by explicitly noting results are informational articles, not referral links, which helps differentiate it from siblings like check_referral_link and inspect_exchange_link.

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?

The description implies when to use this tool: when searching for informational guides by keyword. It explicitly notes the tool is read-only and returns informational articles, not referral links, which helps exclude it from referral-link use cases. However, it doesn't explicitly name alternative tools or state when not to use it, though the sibling list and the 'not referral links' note provide some guidance.

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