update_injury

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

Goes well beyond annotations by disclosing side effects: severity changes are automatically tracked in history, setting end_date auto-marks Resolved, and severity_date backfills history. Also explains that ambiguous selectors cause an error with candidate IDs. These behavioral details are not available in the minimal idempotent/destructive hints.

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 somewhat lengthy due to the selector explanation, but it is well-structured into three logical blocks (purpose/usage, side effects, selector rules) and includes a concrete example for substring matching. It is front-loaded with the core purpose, and every sentence adds necessary information without redundancy.

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?

The description covers essential operational details: default value for severity_date, auto-status behavior, selector ambiguity and error handling, and precedence of id over injury. While it does not describe the response shape, an output schema exists (context signal indicates has output schema: true), so that omission is acceptable. The description is sufficiently complete for a caller to use the tool correctly.

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?

The schema already covers each parameter (100% coverage), so the baseline is 3. The description adds meaningful semantic relationships not evident from individual field descriptions: end_date ↔ status, severity ↔ severity_date, and the selector precedence (date ignored when id is given). This raised the score from baseline.

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?

Clearly states the action and resource: 'Update an existing injury entry.' The description also explicitly lists use cases ('improving, worsening, resolved, or wants to change details'), which fully distinguishes it from siblings like log_injury, list_injuries, and delete_injury without needing to name them.

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?

Provides explicit when-to-use guidance ('Use when the user reports an injury is improving, worsening, resolved, or wants to change details') and explains parameter selection rules (e.g., 'Only send fields that need to change', selector ambiguity and error behavior). It does not explicitly name alternative tools, but the existing-entry phrasing and use-case list make the boundary clear.

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