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

The annotations already indicate the tool is read-only, idempotent, and non-destructive, so the description only needs to add behavioral context beyond safety. It does this by specifying that rates are normalized to a 1-hour rate, that venue interval/open interest/price are included, and that rates are expressed as fractions—useful details that prevent misinterpretation of the returned data.

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 with no filler. The first sentence front-loads the operation, scope, and output components, while the second clarifies the rate unit convention. Every sentence earns its place and the tool's purpose is immediately understandable.

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 single-parameter read-only tool, the description is largely complete: it identifies the input, the per-venue scope, the normalization, and the main output fields. The absence of an output schema is partially mitigated by listing open interest and price, though the exact response structure or venue identifiers are not specified. This is adequate for a simple read operation.

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?

The only parameter, asset, is fully documented in the input schema with a pattern and example, so schema coverage is 100%. The description adds no extra semantic information about the asset parameter beyond the word 'one asset,' which is already reflected in the title and description. Baseline 3 is appropriate because the schema carries the burden.

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 states a specific operation—retrieving the current perpetual funding rate for one asset—and a clear resource scope: each venue that lists the asset. It also names the key returned components (rate, interval, open interest, price), making it easy to identify what this tool does and how it differs from sibling tools that focus on fees, access, or volume.

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 a clear context: use this tool when you need current funding rates for one asset across venues. However, it does not explicitly mention when to prefer an alternative such as get_cheapest_venue or get_venue_fees, nor does it state any exclusions or conditions for not using this tool.

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