container_prune

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

Annotations indicate destructive and idempotent behavior. The description reinforces this by stating it removes containers and notes that running containers are unaffected. It adds filter details and a preview suggestion, providing good behavioral context beyond annotations.

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 paragraph that front-loads the main action. Every sentence serves a purpose: stating the function, constraint, preview alternative, filter details, and sibling reference. No filler.

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 one optional parameter and no output schema, the description covers all necessary aspects: purpose, safety constraints, usage guidance, filter semantics, and return format. It is self-contained and informative.

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 filters parameter is an object with 0% schema coverage. The description compensates by explaining valid filter keys (until, label) and their formats (RFC3339, durations, key=value), adding meaning beyond the empty 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 it removes stopped containers to reclaim disk space. It distinguishes itself from sibling prune tools for other resources and explicitly mentions the 'prune_managed' prompt for broader cleanup.

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?

It specifies that only stopped containers are affected and running containers are never touched. It advises using container_list(all=True) to preview removals and points to the 'prune_managed' prompt as an alternative for broader cleanup.

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