buildx_prune

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

Beyond annotations (destructiveHint=true), the description adds that the tool always uses --force due to no interactive prompt. It also describes the return format. Does not detail what exactly gets removed beyond 'cache entries', but it's sufficient.

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?

Well-structured with a summary, then a warning, then param list, then returns. Every sentence is informative, though a bit lengthy. Could be slightly more concise, but still efficient.

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?

Covers all parameters, return type, destructive behavior, and pairing with sibling. No output schema, but return format is described. Complete given the complexity and annotation coverage.

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 has 0% description coverage, but the description provides a full 'args' section with explanations and examples (e.g., 'filters - Filter by attributes (e.g. {"until": "24h"})'). This fully compensates for the schema's lack.

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 starts with 'Remove BuildKit cache entries', a clear verb-resource pair. It distinguishes from sibling tools like buildx_du by explicitly recommending pairing with it for inventorying.

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?

States to 'Pair with buildx_du first to inventory what would be removed', providing explicit when-to-use guidance. Also warns that --force is always passed, setting expectations for destructive behavior.

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