checkpoint

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

Annotations already declare destructiveHint=true, idempotentHint=false, and readOnlyHint=false; the description complements this by disclosing that it writes under .agentpack/checkpoints and overwrites the pack-level status/next actions that seed the next session. It does not explicitly warn about overwriting prior checkpoint state or state permissions, so it stops short of full disclosure.

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 front-loaded sentences: the first defines what is saved, the second defines when to call it. No filler, and the usage triggers are placed at the end where they are easy to scan.

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 no-required-param, no-output-schema mutation tool, the description covers what is written, where, and when. It omits edge-case behavior such as what happens when all params are empty or how repeated calls interact (relevant given idempotentHint=false), which leaves a minor gap.

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 100% so the baseline is 3, but the description adds meaning by tying 'summary' to progress since the last checkpoint and 'nextActions' to seeding the next session's load_context. It also reveals implicitly captured data (git branch/commit/diff, task id) that are not parameters, which helps the agent understand the write.

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 (Save) plus resource (durable progress checkpoint) and its location (.agentpack/checkpoints), and enumerates what it captures (summary, git state, task id, pack-level status/next actions). This clearly separates it from siblings like load_context, resume, and task_update.

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?

Gives explicit when-to-use triggers (after meaningful progress, before ending a session, before risky changes) and an explicit when-not (not after every small step). It also explains the downstream effect on load_context, so an agent can reason about sequencing.

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