session.checkpoint

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

With no annotations provided, the description bears full responsibility for disclosing behavior. It only mentions capturing 'mesh data + transform' but omits side effects, persistence, overwrite behavior, required permissions, or mode restrictions. This is insufficient for safe usage.

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 sentence that is front-loaded and to the point. It could benefit from slight expansion without becoming verbose, but as is it is 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?

Given no annotations or output schema, the description provides the core purpose but lacks behavioral and parameter details. It is minimally viable but has clear gaps, especially for a tool that likely creates state.

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 input schema includes titles for the two optional parameters ('Checkpoint label...' and 'Object to snapshot...'), but the description adds no further explanation. With schema description coverage reported as 0%, the description should have compensated but did not.

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 action ('Snapshot an object's mesh data + transform') and its purpose ('so an edit can be rolled back'). It distinguishes itself from sibling tools like session.revert (which performs the rollback) and session.list_checkpoints (which lists snapshots).

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 implies usage before editing to enable rollback, but provides no explicit guidance on when to use this tool versus alternatives like session.revert or session.list_checkpoints. No when-not-to-use or prerequisite information is given.

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