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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the agent knows it's a safe read. The description adds value by detailing output (hourly rates, cumulative and average annualized) and default window. No contradictions, but it omits pagination behavior or rate limits.

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 two sentences, front-loaded with the core action and outcome. Every sentence is meaningful: the first specifies what it does, the second gives use case and default. No wasted words.

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?

Given the tool has 5 parameters, robust annotations, and an output schema, the description covers the key aspects: data granularity (hourly), computed fields (cumulative, average annualized), default window, and use case. Missing explicit mention of pagination, but the schema provides bounds on limit/offset. Overall adequate for agent invocation.

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 60%, meaning 3 of 5 parameters have descriptions. The description adds meaning by referencing 'coin' and 'time window' (startTime/endTime) and stating the default. However, it does not cover limit/offset, so the description adds moderate value beyond the schema.

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 clearly states the tool returns 'Historical hourly funding rates for a coin over a time window, with cumulative and average annualized funding.' It specifies the verb (get rates), resource (funding history), and scope (hourly, cumulative, average). Among sibling tools, none duplicate this functionality, so differentiation is inherent.

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 explicitly says 'Use for carry analysis and funding trend,' providing clear context for when to invoke the tool. It also notes the default time window of 7 days. However, it does not mention when not to use it or provide alternative tools, but the sibling list makes it obvious that this is the sole funding history tool.

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