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

Annotations already cover read-only, idempotent, non-destructive behavior, so the description doesn't need to restate those. It adds behavioral context beyond annotations by specifying the APY-history scope and that it targets a single pool. No contradictions; the description is consistent with the read-only annotation.

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?

Three concise sentences, each earning its place: what it does, when it's useful, and which sibling to use for discovery. Front-loaded with the core action; no redundant or filler 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's simplicity (one required param, output schema present, rich annotations), the description is complete. It covers purpose, use case, and sibling routing, while the output schema and parameter schemas supply the remaining invocation details. Nothing essential is missing.

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 100%, with each parameter (days, chain_id, pool_address) already documented. The description does not add any parameter-level meaning beyond what the schema provides, so a baseline 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 states a specific verb and resource: 'Get detailed info for a single lending pool including APY history over time.' It clearly distinguishes this tool from siblings like read_pool_list (discover pool addresses) and write_pool_deposit/redeem (writes). The scope is explicit: one pool, not a list.

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?

It gives concrete guidance on when to use the tool ('analyzing rate trends and comparing pools') and explicitly names the alternative for discovery: 'Use read_pool_list to discover pool addresses.' It doesn't state a formal when-not-to-use condition, but 'single lending pool' implies this is not for listing or multi-pool overviews.

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