Persist the current agent state by saving a checkpoint. Include optional JSON data to capture custom context for later recovery and recall.
Save a checkpoint of current agent state.
| Name | Required | Description | Default |
|---|---|---|---|
| state | No | Optional JSON object with arbitrary state to persist. | |
| agent_id | Yes | The agent to checkpoint. |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate this is not read-only and not idempotent, and the description adds that it persists agent state. However, it does not explain overwrite behavior, whether checkpoints accumulate, or what happens to existing checkpoints. No contradiction with 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?
A single, front-loaded sentence with no filler words. Every word contributes to the meaning.
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?
The tool is simple and parameters are fully documented in the schema, but the description lacks lifecycle context such as whether saving overwrites a previous checkpoint, how it relates to checkpoint_resume, or what the return value is. It is minimally viable but not rich enough to be fully self-sufficient.
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 100%, so the baseline is 3. The description adds no extra meaning about the agent_id or state parameters beyond what the schema already provides.
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' and a specific resource 'checkpoint of current agent state'. The name and description clearly distinguish it from sibling tools like checkpoint_resume and the memory_* tools.
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?
No guidance is given about when to use checkpoint_save versus checkpoint_resume or the memory tools. There are no conditions, exclusions, or alternative routing cues.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.