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

Beyond the readOnlyHint annotation, the description discloses critical behavior: it looks up bids by root, derives trait config from the resulting punk set, returns `resolved: false` for unknown roots, and has a rate limit shared with filter_punks and compute_merkle_root. This adds significant transparency beyond the 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?

The description is concise and well-structured: four sentences each adding essential information—purpose, prerequisite, return behavior, and rate limit. No wasted words or redundancy.

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?

With no output schema, the description explains the return for unknown roots but does not explicitly detail the full positive response structure. However, it names the key contents (punk IDs and trait selection), which is adequate for a single-parameter resolver. The rate limit and prerequisite are also disclosed.

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 schema already provides full parameter coverage (pattern and description for merkleRoot). The description adds semantic constraints: the root must correspond to an existing bid, and locally constructed roots will not work. This provides meaning beyond the schema's format validation.

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's function: 'Reverse-engineer a Merkle root back to its punk IDs and inferred trait selection.' This uses a specific verb and resource, and distinguishes it from siblings like compute_merkle_root, which likely does the forward operation.

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 explicit when-to-use guidance: 'ONLY works for roots that already have at least one bid in the CryptoPunks Bids API' and warns that 'constructing a root locally and passing it here will not work.' This clearly excludes inappropriate use cases and is highly actionable.

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