policy_evaluate

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

With no annotations, the description discloses that the tool is read-only and side-effect free, not writing to the audit log. This is sufficient for safety, though it could mention any required permissions or prerequisites for loading the policy.

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 concise with three sentences. It front-loads the core action and output, followed by usage guidance and safety. No unnecessary words.

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 no output schema, the description explains the return values (matched rule, decision, pattern). It covers purpose, usage, and safety. However, it doesn't specify behavior when no rule matches, which slightly reduces completeness.

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 description coverage is 100%, so the schema already documents both parameters. The main description adds minimal parameter details beyond what the schema provides, such as the dry-run context, but doesn't significantly enhance parameter understanding.

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 states the tool evaluates a policy against a candidate tool name and returns the matched rule, decision, and pattern. It distinguishes itself from siblings policy_list_rules and policy_load_info by focusing on evaluation rather than listing or loading.

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?

Explicitly states when to use: 'dry-run a tool call before issuing it, or to explain why a previous call was blocked.' This provides clear use cases and implies when not to use (e.g., not for listing rules).

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