getChainlinkRoundPrice

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

With no annotations, the description carries the burden of behavioral disclosure. It adds useful detail by describing it as a 'real historical lookup' and naming the underlying function getRoundData, which clarifies the semantics. However, it lacks information on return format, potential errors (e.g., invalid roundId), or access limitations.

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 a single, well-structured sentence that front-loads the core purpose and the key differentiator. Every word earns its place; there is no redundancy or fluff.

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 simple read tool with complete schema descriptions, this is adequate but not fully complete. It clearly conveys the tool's scope and when not to use it, but because there is no output schema, it would benefit from mentioning what the returned round data contains (e.g., price, timestamp). The description does not cover error behavior or edge cases, though these may be less critical for this tool type.

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 input schema already covers all three parameters with descriptions (100% coverage). The description only reinforces the role of roundId by tying it to getRoundData(roundId), which adds minimal value beyond the schema. Baseline score of 3 is appropriate.

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 'Fetches a specific historical Chainlink round via getRoundData(roundId)' — a specific verb, resource, and method. It also distinguishes itself from the latest-round sibling by explicitly noting it is 'not a re-fetch of the latest round.'

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 clear usage context by stating this is for historical lookups and explicitly excluding the latest-round case. It implies the alternative getChainlinkPrice for latest data but does not name it directly. No other usage prerequisites or exclusions are mentioned.

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