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

Annotations already cover the safety profile (readOnly=false, destructive=false, idempotent=false, openWorld=true), so the bar is lower, and the description still adds real value: 'immutable' signals that existing versions are never mutated, and 'bounded receipt' warns that the response is truncated relative to the stored content. It does not mention auth/permission requirements or slug-uniqueness failure behavior, which remain in the schema only.

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?

Two sentences, zero filler, with the action and the immutability/return-size caveat front-loaded before the follow-up routing. Nothing repeats the tool name or title.

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?

With an output schema present, the description does not need to enumerate return fields, and its 'bounded receipt' note usefully frames why the output is partial. For an 8-parameter write tool with full schema coverage and clear annotations, this is close to complete; only sibling differentiation and any permission preconditions are absent.

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 every parameter including the enum on visibility and the odd 'why' field is documented in the schema itself. The description adds nothing about parameter formats or defaults beyond the schema; baseline 3 applies.

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?

States a specific verb and resource ('Deploy a base64 ZIP as an immutable file-tree version'), which tells an agent exactly what is produced and that the result is content-addressed/immutable. It does not distinguish itself from close siblings such as bundle_create_version or artifact_upload, so the boundary between near-identical write tools is left implicit.

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?

'Returns a bounded receipt; bundle_get reads full metadata/manifest and bundle_get_file reads complete files' explicitly routes the agent to the right follow-up tool rather than leaving it to guess. There is no statement of when to prefer this over bundle_create_version, but the read-path guidance is concrete and actionable.

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