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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds genuine context beyond that: the data comes from 'credential-free public market-data JSON', telling the agent no auth is required. It does not mention rate limits, pagination, or what 'normalized' entails, keeping it short of a 5.

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 the purpose, followed by routing to the sibling alternative. Slightly wasteful in that the ticker/series_ticker sentences duplicate the schema descriptions, but overall tight and well ordered.

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?

An output schema exists, so return values need no explanation, and the schema covers the timestamp and interval parameters. Combined with the auth context and sibling routing, an agent has enough to call the tool correctly; only edge-case behavior (empty ranges, interval defaults) is unaddressed.

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%, so the schema already documents all six parameters including the series_ticker default. The description restates ticker and series_ticker almost verbatim, adding no new syntax or format detail, 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 and resource ('Returns normalized Kalshi candlesticks for one market') with an explicit scope of 'one market', which distinguishes it from the batch sibling kalshi_markets_history. An agent can tell what it does and what it does not do 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 names the alternative ('Use kalshi_markets_history to retrieve kalshi batch market history') and the single-market focus selects this tool. It does not state exclusions such as timeframe prerequisites or when the result would be empty, so it stops just short of a full when/when-not rubric.

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