tenki_update_snapshot

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

Annotations already indicate this is not read-only and not destructive. The description adds that only mutable metadata fields are affected and hints at partial updates via 'and/or', but it does not explain behavior when only one field is supplied, potential validation rules, or whether updating expires_at alters existing auto-delete 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?

A single sentence that front-loads the verb and resource, then scopes the exact fields affected. No filler or redundant restatement of the tool name.

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 metadata-update tool with annotations and a decent input schema, the description is mostly sufficient. It could mention partial-update behavior or validation constraints, but the core purpose and parameter meanings are clear enough for correct invocation.

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 already describes name and expires_at, and the description groups them as 'mutable metadata'. The required snapshot_id parameter has no schema description and the description does not clarify it, though it is largely inferable from the tool name. With 67% schema coverage, the description adds some but not complete semantic value.

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?

Description uses a specific verb ('Update') and resource ('a snapshot's mutable metadata'), and immediately narrows scope to name and/or expiry. This clearly distinguishes it from snapshot get/delete/create tools and from other update_* siblings.

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 intended use is implied: modify metadata on an existing snapshot. However, there is no explicit guidance about when to choose this over alternatives, no prerequisite that the snapshot must exist, and no mention of related operations like tenki_create_snapshot or tenki_delete_snapshot.

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