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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds genuinely new behavioral facts the annotations don't: the result is capped at 100 and ordered newest-first, which tells the agent there is no full-history enumeration and no pagination parameter to reach for.

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 tight sentences: capability and result shape first, then the conceptual meaning of a checkpoint and its purpose. Zero filler, and the most decision-relevant facts (cap, ordering, fields) are front-loaded.

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 read-only, single-parameter list tool with no output schema, the description covers what is returned (label, changed paths, timestamp) and the size/ordering limit. It could go one step further by naming restore_checkpoint as the follow-up action, but nothing essential for calling it correctly is missing.

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?

Only one parameter and schema coverage is 100%, so the schema already explains 'id' as a Project UUID. Baseline for a single fully documented parameter is 4; the description adds nothing new about the parameter but loses nothing either.

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+resource ('List a project's saved checkpoints') and adds the scope and shape of results (up to 100, newest first, label/paths/timestamp). It implicitly distinguishes itself from restore_checkpoint by framing the listing as the way to 'undo a bad change', but never names the write sibling, so the differentiation is inferred rather than explicit.

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 line 'Checkpoints are the project's version history — use one to undo a bad change' implies the downstream action but doesn't say when to call list vs. restore_checkpoint, nor any prerequisite like needing a checkpoint id first. Usage is suggested, not instructed.

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