checkpoint_stats

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds only a listing of returned metrics, which largely restates what the output schema provides, and says nothing about cluster resolution behavior or latency/cost of the lookup.

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?

It is a single terse fragment with no filler, so nothing is wasted. But the terseness crosses into under-specification: it reads as a field list rather than a usable instruction.

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-value detail is not strictly needed, yet the description spends its entire budget on return content and leaves the two undocumented input parameters and the tool's usage context unaddressed. For a 2-parameter tool at 0% schema coverage, that is incomplete.

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 description coverage is 0% for both parameters, and the description never mentions job_id (required) or cluster (optional/nullable). With no schema text and no prose, the agent has no documented meaning for either parameter, including what cluster defaults to.

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 names the resource (checkpoints) and the metrics returned (counts, failure rate, last completed/failed), which lets an agent infer this is a read-only stats lookup distinct from list_savepoints. However, it is a noun fragment with no verb, so the actual operation ('get statistics for a job's checkpoints') has to be inferred rather than read.

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?

There is no indication of when to use this versus job_metrics, job_details, or list_savepoints, nor any prerequisite or scoping guidance. The agent must guess that this applies to a single job's checkpointing health.

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