getFundingRateHistory

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

Annotations already signal readOnlyHint=true and openWorldHint=true. The description adds useful behavioral context: records are sorted in reverse chronological order, support covers USDT and Inverse contracts, no authentication is required, and settlement intervals vary by symbol. This goes beyond what the annotations convey.

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 well organized with purpose, use cases, supported products, behavior, and an explicit do-not-use note. The 'Agent hint' section repeats some earlier content, which is mildly redundant, but the structure is clear and the most important guidance is front-loaded.

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 read-only historical query tool with 5 parameters and no output schema, this description is fairly complete: it covers intended use, exclusions, supported products, sort order, time filtering, and authentication. It does not describe limit semantics or output record fields, but those are secondary given the schema already constrains limit.

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 0%, so the description must compensate. It does for the key parameters: category and symbol are called out as required, and startTime/endTime are explained as millisecond filters for narrowing the time range. Limit is not mentioned, but the schema already provides default, min, and max constraints for it.

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 and resource: 'Query historical funding rate records for perpetual contracts.' It also explicitly contrasts itself with getTickers for current funding rates, so an agent can distinguish it from the most relevant sibling without inspecting schemas.

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 gives explicit use cases ('Analyze historical funding rate trends', 'Calculate total funding cost or income', 'Compare funding rates') and an explicit exclusion: 'Do not use this endpoint for the current funding rate — use getTickers.' This is strong routing guidance with an alternative named directly.

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