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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered structurally. The description adds two genuinely useful traits beyond the annotations: 'credential-free' (no API key/auth needed) and 'normalized' (output rows are massaged to a common shape), both of which affect how an agent should plan the call.

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?

A single compact sentence with the key qualifier ('older/historical') front-loaded and zero filler. Every phrase carries information.

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 an output schema present, return values need not be explained, and the read-only/open-world annotations cover the safety profile. The one remaining gap is the lack of routing against the many sibling Kalshi trade/market-history tools, which keeps this just below complete.

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 100% and all five parameters (limit, cursor, max_ts, min_ts, ticker) are documented in the schema itself. The description adds no parameter syntax or format detail beyond that, 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 ('Returns') and resource ('older Kalshi trades') and qualifies the scope with 'older/historical' and the source ('credential-free historical market-data JSON'), which implicitly separates it from the live kalshi_trades sibling. It stops short of naming that sibling, so an agent still has to infer the boundary.

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?

There is no explicit when-to-use or when-not-to-use guidance. The word 'older' implies it is for archived trades versus live ones, but no alternative tool is named and no condition (e.g., after the historical cutoff) is stated.

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