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

Annotations already indicate read-only, idempotent, and non-destructive behavior. The description adds meaningful context beyond annotations by specifying the exact return contents (outcome list, implied probabilities in both OOM and USDC, volumes, tags, description, resolution status) and the keyless auth requirement.

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 purposeful sentences with zero waste: a front-loaded verb+resource, a compact list of return fields, a concrete example id, and the keyless note. Every element 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?

For a one-parameter retrieval tool with no output schema, the description fully covers what the caller can expect, including the market's outcome structure and the specific probability formats. No significant missing context.

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 id parameter has 100% schema coverage, including a clear description and how to obtain ids. The tool description only reiterates 'by id' and provides an example, so it adds no substantial semantics beyond the schema.

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 opens with a specific verb+resource ('Get one Futuur market by id') and enumerates the returned payload, clearly distinguishing it from list/search sibling tools like search_markets and top_markets.

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 for a known market id, but it does not explicitly state when to use this tool versus alternatives or mention that ids come from search_markets/top_markets. That guidance exists in the parameter schema, not in the description itself.

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