command_completions

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. It states the tool returns matches but doesn't describe the return format (e.g., list structure, sorting), performance characteristics (e.g., case sensitivity, partial matching), or any limitations (e.g., max results, rate limits). For a tool with no annotation coverage, this leaves significant gaps in understanding its behavior.

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: 'Return all interactive commands matching a prefix.' It is front-loaded with the core action and resource, with no wasted words. Every part of the sentence contributes directly to understanding the tool's function, making it highly concise and well-structured.

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's low complexity (one parameter, no output schema, no annotations), the description is minimally adequate. It covers the basic purpose but lacks details on usage guidelines, behavioral traits, and output format. For a completion tool in a context with many siblings, more guidance on differentiation and return values would improve completeness, but it meets the minimum viable threshold.

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 input schema has 100% description coverage, with the single parameter 'command_prefix' documented as 'Prefix to match.' The description adds no additional semantic context beyond this, such as examples of valid prefixes or how matching is performed (e.g., substring vs. start-only). With high schema coverage, the baseline score of 3 is appropriate, as the description doesn't compensate but also doesn't detract.

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: 'Return all interactive commands matching a prefix.' It specifies the verb ('Return'), resource ('interactive commands'), and operation ('matching a prefix'), making the function unambiguous. However, it doesn't differentiate from sibling tools like 'function_completions' or 'variable_completions', which likely serve similar completion purposes for different resource types.

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. It doesn't mention sibling tools like 'function_completions' or 'variable_completions', nor does it specify contexts where command completions are preferred over other completion types. There's no information on prerequisites, such as whether commands must be loaded or available in the current session.

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