List checkpoints

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description still earns credit by disclosing a non-obvious data trait: a checkpoint taken before the project was opened reports restorable=false. That is real behavioral context an agent could not derive from the 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?

Two compact sentences with zero filler, and the core identity (these are edit_history's checkpoints, returned as label/changes ago/restorable rows) is front-loaded before the caveat.

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 no parameters and an output schema present, the description needn't restate the return shape, and it covers the one semantic quirk (restorable=false). A small gap remains around what 'changes ago' actually contains, but this is minor for a zero-argument read tool.

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 tool takes zero parameters and the schema is fully described, so there is nothing for the description to compensate for. Baseline 4 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?

The description makes clear it returns the checkpoints recorded by the sibling tool `edit_history`, and names the row shape. The verb is implicit (a noun phrase rather than 'List...'), but the resource and its origin are unambiguous enough to distinguish it from `edit_history` itself.

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?

Usage is only implied: it tells you the output is the set of checkpoints `edit_history` remembered, so an agent can infer this is the read counterpart to that tool. There is no explicit 'use when' statement, no mention of ordering or limits, and no named alternative to compare against.

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