Files
crewAI/docs/en/concepts/checkpointing.mdx
Greyson LaLonde 1293dee241 feat: checkpoint TUI with tree view, fork support, editable inputs/outputs
- Rewrite TUI with Tree widget showing branch/fork lineage
- Add Resume and Fork buttons in detail panel with Collapsible entities
- Show branch and parent_id in detail panel and CLI info output
- Auto-detect .checkpoints.db when default dir missing
- Append .db to location for SqliteProvider when no extension set
- Fix RuntimeState.from_checkpoint not setting provider/location
- Fork now writes initial checkpoint on new branch
- Add from_checkpoint, fork, and CLI docs to checkpointing.mdx
2026-04-10 21:24:49 +08:00

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---
title: Checkpointing
description: Automatically save execution state so crews, flows, and agents can resume after failures.
icon: floppy-disk
mode: "wide"
---
<Warning>
Checkpointing is in early release. APIs may change in future versions.
</Warning>
## Overview
Checkpointing automatically saves execution state during a run. If a crew, flow, or agent fails mid-execution, you can restore from the last checkpoint and resume without re-running completed work.
## Quick Start
```python
from crewai import Crew, CheckpointConfig
crew = Crew(
agents=[...],
tasks=[...],
checkpoint=True, # uses defaults: ./.checkpoints, on task_completed
)
result = crew.kickoff()
```
Checkpoint files are written to `./.checkpoints/` after each completed task.
## Configuration
Use `CheckpointConfig` for full control:
```python
from crewai import Crew, CheckpointConfig
crew = Crew(
agents=[...],
tasks=[...],
checkpoint=CheckpointConfig(
location="./my_checkpoints",
on_events=["task_completed", "crew_kickoff_completed"],
max_checkpoints=5,
),
)
```
### CheckpointConfig Fields
| Field | Type | Default | Description |
|:------|:-----|:--------|:------------|
| `location` | `str` | `"./.checkpoints"` | Storage destination — a directory for `JsonProvider`, a database file path for `SqliteProvider` |
| `on_events` | `list[str]` | `["task_completed"]` | Event types that trigger a checkpoint |
| `provider` | `BaseProvider` | `JsonProvider()` | Storage backend |
| `max_checkpoints` | `int \| None` | `None` | Max checkpoints to keep. Oldest are pruned after each write. Pruning is handled by the provider. |
| `restore_from` | `Path \| str \| None` | `None` | Path to a checkpoint to restore from. Used when passing config via a kickoff method's `from_checkpoint` parameter. |
### Inheritance and Opt-Out
The `checkpoint` field on Crew, Flow, and Agent accepts `CheckpointConfig`, `True`, `False`, or `None`:
| Value | Behavior |
|:------|:---------|
| `None` (default) | Inherit from parent. An agent inherits its crew's config. |
| `True` | Enable with defaults. |
| `False` | Explicit opt-out. Stops inheritance from parent. |
| `CheckpointConfig(...)` | Custom configuration. |
```python
crew = Crew(
agents=[
Agent(role="Researcher", ...), # inherits crew's checkpoint
Agent(role="Writer", ..., checkpoint=False), # opted out, no checkpoints
],
tasks=[...],
checkpoint=True,
)
```
## Resuming from a Checkpoint
Pass a `CheckpointConfig` with `restore_from` to any kickoff method. The crew restores from that checkpoint, skips completed tasks, and resumes.
```python
from crewai import Crew, CheckpointConfig
crew = Crew(agents=[...], tasks=[...])
result = crew.kickoff(
from_checkpoint=CheckpointConfig(
restore_from="./my_checkpoints/20260407T120000_abc123.json",
),
)
```
Remaining `CheckpointConfig` fields apply to the new run, so checkpointing continues after the restore.
You can also use the classmethod directly:
```python
config = CheckpointConfig(restore_from="./my_checkpoints/20260407T120000_abc123.json")
crew = Crew.from_checkpoint(config)
result = crew.kickoff()
```
## Forking from a Checkpoint
`fork()` restores a checkpoint and starts a new execution branch. Useful for exploring alternative paths from the same point.
```python
from crewai import Crew, CheckpointConfig
config = CheckpointConfig(restore_from="./my_checkpoints/20260407T120000_abc123.json")
crew = Crew.fork(config, branch="experiment-a")
result = crew.kickoff(inputs={"strategy": "aggressive"})
```
Each fork gets a unique lineage ID so checkpoints from different branches don't collide. The `branch` label is optional and auto-generated if omitted.
## Works on Crew, Flow, and Agent
### Crew
```python
crew = Crew(
agents=[researcher, writer],
tasks=[research_task, write_task, review_task],
checkpoint=CheckpointConfig(location="./crew_cp"),
)
```
Default trigger: `task_completed` (one checkpoint per finished task).
### Flow
```python
from crewai.flow.flow import Flow, start, listen
from crewai import CheckpointConfig
class MyFlow(Flow):
@start()
def step_one(self):
return "data"
@listen(step_one)
def step_two(self, data):
return process(data)
flow = MyFlow(
checkpoint=CheckpointConfig(
location="./flow_cp",
on_events=["method_execution_finished"],
),
)
result = flow.kickoff()
# Resume
config = CheckpointConfig(restore_from="./flow_cp/20260407T120000_abc123.json")
flow = MyFlow.from_checkpoint(config)
result = flow.kickoff()
```
### Agent
```python
agent = Agent(
role="Researcher",
goal="Research topics",
backstory="Expert researcher",
checkpoint=CheckpointConfig(
location="./agent_cp",
on_events=["lite_agent_execution_completed"],
),
)
result = agent.kickoff(messages=[{"role": "user", "content": "Research AI trends"}])
```
## Storage Providers
CrewAI ships with two checkpoint storage providers.
### JsonProvider (default)
Writes each checkpoint as a separate JSON file. Simple, human-readable, easy to inspect.
```python
from crewai import Crew, CheckpointConfig
from crewai.state import JsonProvider
crew = Crew(
agents=[...],
tasks=[...],
checkpoint=CheckpointConfig(
location="./my_checkpoints",
provider=JsonProvider(), # this is the default
max_checkpoints=5, # prunes oldest files
),
)
```
Files are named `<timestamp>_<uuid>.json` inside the location directory.
### SqliteProvider
Stores all checkpoints in a single SQLite database file. Better for high-frequency checkpointing and avoids many small files.
```python
from crewai import Crew, CheckpointConfig
from crewai.state import SqliteProvider
crew = Crew(
agents=[...],
tasks=[...],
checkpoint=CheckpointConfig(
location="./.checkpoints.db",
provider=SqliteProvider(),
max_checkpoints=50,
),
)
```
WAL journal mode is enabled for concurrent read access.
## Event Types
The `on_events` field accepts any combination of event type strings. Common choices:
| Use Case | Events |
|:---------|:-------|
| After each task (Crew) | `["task_completed"]` |
| After each flow method | `["method_execution_finished"]` |
| After agent execution | `["agent_execution_completed"]`, `["lite_agent_execution_completed"]` |
| On crew completion only | `["crew_kickoff_completed"]` |
| After every LLM call | `["llm_call_completed"]` |
| On everything | `["*"]` |
<Warning>
Using `["*"]` or high-frequency events like `llm_call_completed` will write many checkpoint files and may impact performance. Use `max_checkpoints` to limit disk usage.
</Warning>
## Manual Checkpointing
For full control, register your own event handler and call `state.checkpoint()` directly:
```python
from crewai.events.event_bus import crewai_event_bus
from crewai.events.types.llm_events import LLMCallCompletedEvent
# Sync handler
@crewai_event_bus.on(LLMCallCompletedEvent)
def on_llm_done(source, event, state):
path = state.checkpoint("./my_checkpoints")
print(f"Saved checkpoint: {path}")
# Async handler
@crewai_event_bus.on(LLMCallCompletedEvent)
async def on_llm_done_async(source, event, state):
path = await state.acheckpoint("./my_checkpoints")
print(f"Saved checkpoint: {path}")
```
The `state` argument is the `RuntimeState` passed automatically by the event bus when your handler accepts 3 parameters. You can register handlers on any event type listed in the [Event Listeners](/en/concepts/event-listener) documentation.
Checkpointing is best-effort: if a checkpoint write fails, the error is logged but execution continues uninterrupted.
## CLI
The `crewai checkpoint` command gives you a TUI for browsing, inspecting, resuming, and forking checkpoints. It auto-detects whether your checkpoints are JSON files or a SQLite database.
```bash
# Launch the TUI — auto-detects .checkpoints/ or .checkpoints.db
crewai checkpoint
# Point at a specific location
crewai checkpoint --location ./my_checkpoints
crewai checkpoint --location ./.checkpoints.db
```
<Frame>
<img src="/images/checkpointing.png" alt="Checkpoint TUI" />
</Frame>
The left panel is a tree view. Checkpoints are grouped by branch, and forks nest under the checkpoint they diverged from. Select a checkpoint to see its metadata, entity state, and task progress in the detail panel. Hit **Resume** to pick up where it left off, or **Fork** to start a new branch from that point.
### Editing inputs and task outputs
When a checkpoint is selected, the detail panel shows:
- **Inputs** — if the original kickoff had inputs (e.g. `{topic}`), they appear as editable fields pre-filled with the original values. Change them before resuming or forking.
- **Task outputs** — completed tasks show their output in editable text areas. Edit a task's output to change the context that downstream tasks receive. When you modify a task output and hit Fork, all subsequent tasks are invalidated and re-run with the new context.
This is useful for "what if" exploration — fork from a checkpoint, tweak a task's result, and see how it changes downstream behavior.
### Subcommands
```bash
# List all checkpoints
crewai checkpoint list ./my_checkpoints
# Inspect a specific checkpoint
crewai checkpoint info ./my_checkpoints/20260407T120000_abc123.json
# Inspect latest in a SQLite database
crewai checkpoint info ./.checkpoints.db
```