buildx_history_list

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

Annotations already mark it read-only and non-destructive. The description adds value beyond annotations by disclosing the parsing behavior (from --format '{{json .}}'), the exact return structure (list of dicts with fields), and a version-specific error condition. This gives the agent useful operational knowledge.

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 well-structured and concise: a clear main sentence, a brief elaboration on contents and use case, a version requirement note, and a compact args/returns layout. No superfluous 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?

For a simple read-only tool with one optional parameter and no output schema, the description provides the return structure, parameter default, and version prerequisite. It fully prepares the agent to understand what the tool does and what to expect.

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 coverage is 0% (no description on the builder parameter), but the description compensates by explaining the arg: 'Builder instance to read history from (defaults to the active builder)'. This adds meaningful semantic context beyond the raw schema.

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 function: 'List recent build records (BuildKit build history)', with specific details on the output format and fields. It distinguishes itself from sibling buildx_history_inspect by explaining it's the precursor to drill into a specific build.

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 clear usage context: it's useful for finding a build to inspect with buildx_history_inspect, and explicitly notes the version requirement and error behavior for older buildx. It does not exhaustively list when not to use it, but the primary use case is well covered.

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