funding_rates_history

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

With no annotations, the description carries the full burden, and it delivers substantial behavioral context: data sources (Gate.io, MEXC, Kraken), snapshot methodology, sentiment thresholds, cold-start omission, and a 5-minute cache. It still does not describe the exact response structure or error behaviors, but it discloses far more than the minimum.

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 dense but well organized: it front-loads the core purpose, then covers sources, token scope, return contents, sentiment logic, usage example, and caching. Each section adds useful context, though the usage line partly repeats schema defaults.

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 two-parameter tool with no annotations and no output schema, the description covers inputs, defaults, supported tokens, output components, data availability behavior, and cache freshness. The days-bound mismatch with the schema is a notable completeness gap, but overall the agent has enough context to call the tool correctly in most cases.

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 contradictory constraints: it says 'max 180' and 'days is 1–180' while the schema's days parameter has 'maximum': 90. This ambiguity can cause an agent to issue invalid requests. The symbol list adds modest value, but the conflicting range is a serious defect.

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: 'Returns the daily historical perpetual futures funding rate for a single token over the last N days.' It also defines the exact token universe and per-day contents, which distinguishes it from a simple current-rate tool like the sibling funding_rates.

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 provides a clear invocation example ('Use ?symbol=BTC&days=30') and practical defaults, but it never explicitly explains when this tool is preferable to alternatives or when funding_rates/live_stats should be used instead. Usage context is implied by the word 'history' rather than stated.

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