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

With no annotations, the description carries the behavioral burden and is largely successful: it discloses authentication requirements, plan-level eligibility, the api_key fallback, and the project/vault scoping. It does not describe response shape or ordering, but the operation is clearly a read and no hidden effects are implied.

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 three front-loaded sentences: the first states purpose and scope, the second covers plan eligibility, and the third covers auth fallback. Every sentence earns its place with no filler or repeated tool name.

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?

Together with the detailed schema, the description covers selection, filters, pagination, plan requirements, and authentication. The main gap is the absence of an explicit return format or ordering, and there is no output schema to compensate. This is a moderate gap for a history read, but the tool is still callable correctly with the provided information.

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?

All 9 parameters are already covered with descriptions in the schema, so the baseline is 3. The tool description mostly restates the oneOf constraint and the api_key fallback, both of which are already present in the schema. It adds little semantic meaning beyond what an agent can already read from the parameter definitions.

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 opens with a concrete action and resource: 'Returns git commit history for a project (all vaults) or a single vault.' It explicitly distinguishes the two scopes, avoiding tautology and separating this from sibling tools focused on reports, scans, or vault metadata.

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 states when the tool applies and gives a clear selection rule: provide exactly one of project_id or vault_id. It also provides when-not guidance by excluding verification-only plans and requiring full data access, plus an auth fallback for header-less clients. No sibling tool competes for this commit-history use case, so alternative routing is not needed.

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