Codex Code Review

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. The description states it 'Returns specific, actionable feedback,' which indicates the output nature. However, it doesn't disclose that this delegates to an external LLM service (Codex), potential latency/rate-limit behavior, or what 'review' entails operationally. The phrase 'Ask Codex' does hint at external delegation, providing some transparency.

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 a single, efficient sentence (plus a return-value note) that conveys the core purpose without waste. It front-loads the verb and resource, immediately establishing what the tool does. It's appropriately sized-nothing extraneous, though it could arguably mention a sibling alternative for differentiation without becoming verbose.

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?

For a moderately complex tool with 5 parameters and no output schema, the description provides the essential purpose and input modalities but lacks depth. It doesn't clarify expected return format (actionable feedback presumably, but structure is unknown), doesn't describe threading behavior beyond what the schema's threadKey field implies, and doesn't caution about external-service behavior. The description is adequate but leaves gaps for an agent to make informed decisions about invocation.

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 80%, so most parameters are already documented in the schema itself. The description adds value by clarifying the 'target' parameter's three acceptable forms (git diff range, file paths, code snippet) with a concrete example ('HEAD~3..HEAD'), which goes beyond the schema's description. The 'context' and 'focusAreas' parameters are self-explanatory in the schema, and the description doesn't need to add much there.

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 a clear verb+resource ('Ask Codex to review code') and identifies three input modalities (git diff range, file paths, code snippet). However, it doesn't distinguish from sibling tools like codex_explain_code or codex_query, which also involve Codex code interaction. The purpose is clear on what the tool does but not clearly differentiated from its siblings.

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 implies usage context through the input modality examples (diff range, file paths, snippet), which hints at when this tool applies. However, there is no explicit when-to-use guidance, no exclusions, and no mention of alternatives like codex_explain_code for explanation-focused queries versus codex_review_code for actionable review feedback. Usage context is implied but not explicitly stated.

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