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

Annotations already indicate read-only and idempotent behavior, but the description adds substantial behavioral context beyond them: source-branch fetching with fallback to indexed version and notification of fallback, BP findings from a deterministic server-side rule set rather than xppbp.exe, and required credentials/index prerequisites. This transparency goes far beyond what annotations alone convey.

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 well-structured and front-loaded with 'WHEN:', followed by a compact summary of outputs, constraints, and alternatives. It contains no filler, though the trigger-phrase list and some parenthetical rationale add length that may be only marginally necessary.

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?

Despite lacking an output schema, the description explains what the response contains, how source is fetched, fallback behavior, why xppbp.exe cannot be used, required environment variables and scopes, and how to use the tool with a sibling. This gives an agent everything needed to invoke it correctly and interpret results.

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 parameters like prId, project, repositoryId, and maxDeepAnalysis are already well documented in the schema. The description does not add additional parameter-level meaning beyond the schema, so baseline 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?

The description clearly identifies the tool's purpose: reviewing PRs that modify X++ code or AOT objects for D365-specific insights, and explicitly states what it returns (structured code review with blast radius, best-practice violations, impact severity). It also differentiates itself from find_error_patterns, helping an agent distinguish this tool from a related one.

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 opens with 'WHEN: reviewing a PR that modifies X++ code or AOT objects', giving explicit usage context. It also provides routing guidance by saying 'Use find_error_patterns for Microsoft rule text' and suggests combining with ado_post_pr_comment. It lacks explicit exclusion of non-X++ PRs or contrast with other impact-analysis siblings, but the guidance is strong.

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