add_evidence

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

With no annotations, the description carries the full burden. It discloses a key behavioral trait: evidence does NOT contribute to implementation status, only assertions do. However, it does not mention potential side effects, error conditions, or idempotency. Given the tool's simplicity, this is adequate but not rich.

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 extremely concise: two sentences with no redundancy. The first sentence states the purpose, the second clarifies a critical behavioral point. Every word adds value, making it highly efficient.

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?

Given the existence of an output schema, the description need not explain return values. It covers the core action and the key caveat about status. It lacks details on prerequisites (e.g., control must exist) but is otherwise complete for a straightforward metadata-attachment tool.

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 high (83%), so the baseline is 3. The description adds overall context that the parameters are for attaching metadata that doesn't affect status, but it does not detail individual parameters beyond what the schema provides. Thus, it meets the baseline without exceeding it.

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 purpose: 'Attach auxiliary metadata to a control (docs, links, artifacts).' It specifies the action (attach), the resource (control), and the type of data (auxiliary metadata). This distinguishes it from sibling tools like 'add_asset' or 'submit_assertions' because it emphasizes that evidence is not assertion.

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 explicitly states when to use this tool: to attach contextual metadata that does not affect implementation status. It contrasts evidence with assertions ('Only assertions prove controls'), indicating that for status changes, one should use assertion-related tools. While it does not name specific siblings, the conceptual guidance is clear.

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