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

Annotations only cover read-only safety, and the description adds substantial operational context: attestation format (canonical-JSON SHA-256 plus optional Ed25519 signature over the record without its attestation field), latency semantics and the not_measured null case, and access control (USD free, all other currencies return subscription_required with a subscribe link). None of this is available in the structured fields.

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?

Front-loaded with purpose and mode behavior, then structured into discrete concerns (record contents, attestation, timing, access). Dense but nearly every sentence carries non-redundant information; only the latency explanation is somewhat elaborate for the value it adds.

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 9-parameter, no-required-argument tool with an output schema, the description covers invocation modes, parameter interplay, data semantics, signing/verification, timing fields, and access restrictions. An agent has everything needed to call it correctly, and the output schema handles return structure.

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% so the baseline is 3, but the description adds real meaning about parameter interaction: currency+indicator used together, announcement_id used with currency and indicator instead of period, contract_id drawn from the template list, and comparison defaulting to above with resolves_yes outcomes. This goes beyond what the schema strings convey.

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 and resource ('Return the settlement record for an event contract') and immediately scopes it to a Kalshi/Polymarket-style contract on an official macro release. It also enumerates the tool's distinct operating modes (template listing, signing keys, settlement lookup), so an agent understands exactly what it is without opening the 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?

Explicitly explains mode selection: with no contract_id/currency/indicator it lists templates, and with signing_keys=true it returns public keys. It also notes a market's own rules govern settlement and that access differs by currency, but it does not name a sibling tool as an alternative for related queries.

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