zig_std

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

With no annotations provided, the description carries the burden. It honestly discloses how it works: walking real re-exports and returning doc comments plus declaration text from the exact release. This gives the agent a clear model of behavior and scope. It does not mention side effects, but as a lookup tool, that is expected. No contradictions with annotations (none exist).

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: the first sentence states purpose, the second explains the two modes, and the third gives a preference hint. Every sentence earns its place, and there is no verbose repetition or fluff.

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 documentation lookup tool, the description covers the core behavior and most parameters. The output schema exists, so return values need not be described. The main missing piece is the 'force' parameter's effect, which is a notable hole given the tool's simplicity. Overall, it is reasonably complete but not fully exhaustive.

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 0%, so the description must explain parameters. It explains symbol and query with concrete examples, and channel is implied in the first sentence. However, the 'force' parameter is completely unexplained. With four parameters, leaving one entirely undefined is a notable gap, though the primary modes are well covered.

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 it provides standard-library docs from a specific channel's released source. It distinguishes itself from siblings like zig_langref and zig_changelog by specifying the resource (standard library) and the operation (returns /// docs and declaration text). The two modes (symbol lookup and query search) are explicitly described.

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?

It provides guidance on when to use symbol vs query ('Prefer exact symbols; use query to discover names'), which helps within the tool. However, it does not explicitly mention alternatives or when not to use this tool (e.g., versus zig_search or zig_langref). The guidance is implied by the tool's focus on std docs, but it lacks explicit exclusion or alternative routing.

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