delimit_external_pr_check

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

With no annotations provided, the description fully discloses side effects ('read-only network call'), implementation detail ('shells out to gh CLI'), and behavior ('any open PR or PR merged in last 30 days yields verdict=duplicate'). Also mentions 'fail-closed by design'.

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 and well-structured with clear sections (purpose, when to use, when not, sibling contrast, side effects). Every sentence is informative and earns its place.

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 full schema coverage and the presence of an output schema, the description is complete. It covers purpose, usage, side effects, and even hints at the output format ('verdict=duplicate'). No gaps.

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% with clear descriptions for all three parameters (repo, author, state). The description adds no extra parameter semantics beyond what the schema provides, so baseline 3 is appropriate.

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 as a 'Pre-PR duplicate guard for external repos' and distinguishes it from the sibling 'delimit_gov_evaluate' which wraps this function with policy evaluation. The verb 'guard' and resource 'duplicate check' are specific.

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 provides when to use ('first step before drafting any PR against a repo you don't own') and when not to use ('internal repos or non-PR action'), along with an alternative tool ('delimit_gov_evaluate'). This is thorough guidance.

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