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

Annotations already declare readOnly and idempotent, so the description adds valuable context beyond structured data: it specifies return contents (per-outcome implied probabilities in both OOM and USDC modes), the default status filter, and notes that no authentication is needed (keyless). These details paint a fuller behavioral picture without contradicting annotations, though pagination or error behavior not mentioned.

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: the first front-loads the core action, and the second adds key defaults and return details. Every piece of information earns its place, with no redundancy or fluff. It remains compact while covering the essential facts.

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?

Given the tool complexity (4 params, no output schema, strong annotations), the description adequately covers the main purpose, default behavior, currency modes, and auth. It does not mention return structure in depth or alternatives, but for a read-only search tool with a rich schema, it is sufficiently complete. A minor gap is the lack of note about 'omit to browse' which is left to the schema.

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% (all 4 parameters described), so the description is not required to compensate. It does add context around currency modes ('play-money (OOM) and real-money (USDC)') which ties to 'currency_mode', but it doesn't introduce meaning beyond the schema's own detailed descriptions. Baseline 3 is appropriate.

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 a specific verb and resource: 'Search Futuur prediction markets by text', with a defined scope (politics, crypto, sports, science) and a default behavior (open markets). This distinguishes it from siblings like 'get_market' or 'top_markets' which are more specific or ranked, making the search intent explicit.

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 usage via 'Search ... by text' and mentions keyless access and default status, but does not explicitly contrast with alternative tools like 'top_markets' or 'get_market', nor does it state when not to use this tool. For a search tool, the context is clear but exclusions are absent, so it remains at the implied-usage level.

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