vxcontrol/pentagi · error
failed to get coder handler
Error message
failed to get coder handler: %w
What it means
Wraps a failure from fp.GetCoderHandler during assistant worker setup (backend/pkg/providers/assistant.go). The coder (developer agent) LLM handler could not be constructed, typically because the configured primary LLM provider is unavailable or misconfigured. The assistant worker cannot start without it.
Solutions
- Check Docker availability: `docker ps` from inside the backend container and verify /var/run/docker.sock is mounted/permissioned.
- Set required tool env vars and restart the backend.
- Inspect the wrapped error in logs to identify the failing sub-tool.
- Run the installer wizard to complete tool configuration.
Example fix
// before
coder, err := ap.fp.GetCoderHandler(ctx, nil, nil)
if err != nil {
return fmt.Errorf("failed to get coder handler: %w", err)
}
// after
coder, err := ap.fp.GetCoderHandler(ctx, &taskID, &subtaskID)
if err != nil {
logger.WithError(err).Error("coder handler init failed — check docker socket & tool env")
return fmt.Errorf("failed to get coder handler: %w", err)
} Defensive patterns
Strategy: validation
Validate before calling
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil { return fmt.Errorf("docker unavailable for coder handler: %w", err) }
_ = cli Try / catch
coder, err := ap.fp.GetCoderHandler(ctx, nil, nil)
if err != nil {
logger.WithError(err).Error("coder handler init failed — check docker")
return fmt.Errorf("failed to get coder handler: %w", err)
} Prevention
- Verify `docker ps` works inside the backend container
- Check /var/run/docker.sock ownership (998:998 or root)
- Pre-pull the sandbox coding image
- Set DOCKER_HOST explicitly in remote deployments
When it happens
Trigger: Coder handler construction fails: Docker sandbox client cannot initialize, required tool configuration/env missing, or underlying DB/template lookups error.
Common situations: Docker socket inaccessible (permission denied on /var/run/docker.sock); DOCKER_HOST misconfigured; missing env config for coding tools; fresh deployment with incomplete .env.
Related errors
- failed to get installer handler
- failed to get pentester handler
- failed to get ask advice handler
- code result handler is required
- command execution timeout
AI-assisted analysis of vxcontrol/pentagi@ea665308ba (2026-09-01).
Data as JSON: /api/errors/0ea0deb024cd771a.
Report an issue: GitHub.
Appendix: source
Thrown at backend/pkg/providers/assistant.go:171
return fmt.Errorf("failed to get primary agent msg chain %d: %w", ap.msgChainID, err)
}
var chain []llms.MessageContent
if err := json.Unmarshal(msgChain.Chain, &chain); err != nil {
logger.WithError(err).Error("failed to unmarshal primary agent msg chain")
return fmt.Errorf("failed to unmarshal primary agent msg chain %d: %w", ap.msgChainID, err)
}
adviser, err := ap.fp.GetAskAdviceHandler(ctx, nil, nil)
if err != nil {
logger.WithError(err).Error("failed to get ask advice handler")
return fmt.Errorf("failed to get ask advice handler: %w", err)
}
coder, err := ap.fp.GetCoderHandler(ctx, nil, nil)
if err != nil {
logger.WithError(err).Error("failed to get coder handler")
return fmt.Errorf("failed to get coder handler: %w", err)
}
installer, err := ap.fp.GetInstallerHandler(ctx, nil, nil)
if err != nil {
logger.WithError(err).Error("failed to get installer handler")
return fmt.Errorf("failed to get installer handler: %w", err)
}
memorist, err := ap.fp.GetMemoristHandler(ctx, nil, nil)
if err != nil {
logger.WithError(err).Error("failed to get memorist handler")
return fmt.Errorf("failed to get memorist handler: %w", err)
}
pentester, err := ap.fp.GetPentesterHandler(ctx, nil, nil)
if err != nil {
logger.WithError(err).Error("failed to get pentester handler")
return fmt.Errorf("failed to get pentester handler: %w", err)View on GitHub (pinned to ea665308ba)