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

No annotations exist, so the description carries the full burden. It usefully discloses that the tool is 'Deterministic' and that it produces a 'token delta,' which are meaningful behavioral traits beyond a generic review. However, 'token delta' is never explained (metering? cost report? persistence?), and the description does not state whether the tool has side effects, requires auth, or how workspace is used.

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 compact sentences with the core purpose front-loaded in the first sentence and the usage directive last. Every sentence earns its place, though the cryptic phrases 'Deterministic doctor' and 'token delta' slightly undermine clarity in an otherwise tight definition.

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 annotations and no output schema, the description must carry more weight, and it falls short. It does state the return contract, but two of four parameters (files, workspace) are unexplained, the token-delta side effect is ambiguous, and there is no statement of read-only versus mutating behavior, leaving an agent to guess at invocation semantics.

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 coverage is 50%: diff and config have descriptions, but files and workspace do not. The description reinforces the central relationship ('review a git unified diff against architecture.hexum') but does not clarify how diff and files interact, what workspace means, or when config is needed beyond what the schema already states.

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 and resource: 'Review a git unified diff against architecture.hexum,' and lists concrete return values (approved|changes_requested, violations, GitHub-ready markdown review). The purpose is clear and recognizable against the sibling names, though it does not explicitly name or contrast a sibling tool.

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 an explicit preference directive: 'Prefer this over asking the model to review architecture,' which tells the agent when to choose this tool over a model-mediated general review. However, it offers no exclusions and does not distinguish when hexum_check or other siblings would be more appropriate.

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