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

readOnlyHint=true already covers the safety profile, so the description earns credit for adding beyond it: it discloses the severity model, that a 'fatal' pipeline cannot be planned, and the notable error behavior that unreadable YAML returns a fatal violation rather than a tool error. No auth/rate-limit context, but a material failure-mode detail is provided.

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?

Front-loads purpose, then return shape, then failure semantics, closing with a read-only note. Four short sentences with no filler, and each earns its place given there is no output schema to carry the return description.

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 takes on the return-value burden and does so fully (severity values, violations with classifier key and message, declared name, stages in order, trigger events) while also covering when to use and the fatal failure mode. 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?

Schema coverage is 100% and the single parameter is fully documented as the full contents of the .ankra/pipeline.yaml document. The description adds no syntax or format detail beyond the schema, so the baseline of 3 applies.

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 (Validate) and resource (Ankra pipeline definition, .ankra/pipeline.yaml) and explicitly contrasts itself with the sibling cicd_validate_workflow_yaml ('the twin ... for the definition that replaces the GitHub Actions workflow'). An agent can tell the two apart without opening either schema.

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 clear context ('before proposing or committing it') and names the alternative (cicd_validate_workflow_yaml) plus the condition that selects between them (pipeline.yaml vs GitHub Actions workflow). It does not enumerate when not to use it, but the sibling routing is explicit enough to guide selection.

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