blender.checkpoint

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

With no annotations, the description carries the burden and does well: it explains the effect ('a later rollback can stop there instead of unwinding everything') and the consequence for partial work ('discards only the details'). It does not state what happens if no transaction is open or if the label already exists, so minor gaps remain.

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?

Front-loaded with purpose, followed by a compact worked example and a one-line parameter note. Every sentence earns its place, though the build-stage example is slightly more verbose than strictly necessary.

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?

An output schema exists, so return values need not be explained, and the description covers purpose, workflow, and the one parameter's constraint. It omits edge-case behavior (no open transaction, duplicate label), which would round it out fully.

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%, so the description must compensate; it adds the key constraint that 'label' is required and 'unique within the transaction', which the bare string schema does not convey. However, it gives no format or syntax guidance, leaving the compensation partial.

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 states a specific verb and resource ('Record a named point inside the open transaction') and immediately clarifies its role relative to rollback. An agent can distinguish it from begin_transaction, commit_transaction, and rollback_transaction without opening any schema.

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 gives an explicit usage pattern ('begin -> build the shell -> checkpoint "shell" -> add the details -> commit') that makes the when-to-use condition concrete. It does not name when-not-to-use or explicitly contrast with sibling tools, so it falls just short of a 5.

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