hash

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

Annotations cover the safety profile (readOnly, idempotent, closed-world), so the description's job is to add beyond that. It does: determinism guarantees identical hashes across machines for identical code, and it discloses the failure mode (errors when the repo is not enrolled). It does not cover latency or hashing scope limits, but the added context is substantial.

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 tight sentences, front-loaded with what is returned before the usage guidance and the error condition. No sentence is filler.

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?

There is no output schema, so the description carries the return-value burden and does so ('root hash + file count'), plus the determinism contract and the not-enrolled error. For a single-param, read-only tool, nothing needed to call it correctly 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?

Only one parameter, fully documented in the schema (100% coverage), so the schema does the heavy lifting. The description only implicitly clarifies that `repo` must be enrolled ('an enrolled repo', 'Errors if the repo is not enrolled'), adding marginal value over the schema's 'name of an enrolled repo'.

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?

States a specific verb+resource: computes a deterministic root hash plus file count for an enrolled repo's current code. It also names the sibling it relates to (`status`'s stored hash), so an agent can distinguish it from `diff`, `structure`, `health`, or `locate`.

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?

Gives explicit when-to-use conditions: to confirm two machines/checkouts hold identical code, or that code changed since a stored hash. It also names the alternative source of comparison (`status`'s latest stored hash), which is exactly the routing information an agent needs.

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