check

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

In the absence of annotations, the description discloses that lint returns a structured findings list, and it warns that dry-activate is NixOS only. However, it does not explicitly state that the tool is read-only, does not discuss side effects or permissions, and leaves the behavior of mode and flake_uri unaddressed.

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, front-loaded sentence that efficiently conveys the core purpose and lists the level options with specific details. No wasted 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 the tool has three parameters and no annotations, the description explains the primary parameter (level) well and the overall workflow, but the silence on mode and flake_uri leaves a significant semantic gap. The presence of an output schema reduces the need to describe return values, but the overall context is only moderately complete.

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?

The description defines the possible values for the required 'level' parameter, giving meaningful semantics to lint, dry-build, and dry-activate. However, it says nothing about the 'mode' or 'flake_uri' parameters, which are left entirely to the schema's bare property names and defaults, so schema coverage is effectively 0% and the description does not compensate.

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 defines 'check' as a validation ladder for the configuration with three specific levels (lint, dry-build, dry-activate), each with a distinct verb and outcome. It distinguishes from sibling tools like 'build' and 'switch' by focusing on validation rather than execution.

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 phrase 'fast to slow' establishes a clear progression for when to use each level, and the explicit context for 'dry-activate' (NixOS only) provides a constraint. However, it does not explicitly contrast with sibling tools or state when to avoid this tool in favor of alternatives.

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