search_nix_packages

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

No annotations are provided, so the description carries the full burden. It mentions what the tool returns (packages with versions, descriptions, maintainers) but lacks important behavioral details like whether this is a read-only operation, if it requires authentication, rate limits, pagination behavior beyond the parameters, or error conditions. The description provides basic output information but misses key operational context.

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 extremely concise with just two sentences that efficiently convey the core functionality and return values. Every word earns its place with zero wasted text. The structure is front-loaded with the primary purpose followed by output details.

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 search tool with 3 parameters, 100% schema coverage, but no annotations and no output schema, the description provides basic purpose and output information. However, it lacks important context about behavioral traits, error handling, and usage guidelines. The description is minimally adequate but has clear gaps in completeness given the tool's complexity and lack of supporting structured data.

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 the schema already fully documents all three parameters. The description doesn't add any parameter-specific information beyond what's in the schema. It mentions searching 'by query' which aligns with the 'query' parameter but doesn't provide additional semantic context. The baseline of 3 is appropriate when the schema does all the parameter documentation work.

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: 'Search for Nix packages by query' with the verb 'search' and resource 'Nix packages'. It distinguishes from the sibling tool 'search_nixos_options' by specifying packages rather than options. However, it doesn't explicitly mention the sibling differentiation in the text itself.

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 provides no guidance on when to use this tool versus alternatives. There's no mention of the sibling tool 'search_nixos_options' or any other potential alternatives. The description simply states what the tool does without contextual usage information.

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