The short version
- Countersign fits LangGraph teams that want to own the approval boundary, policy, provenance, and evidence.
- Agent Inbox is the closest starting point for graphs already using its HumanInterrupt shape. Countersign accepts that shape for incremental migration.
- gotoHuman fits teams prioritizing a managed, framework-agnostic review platform and existing hosted integrations.
Side by side
| Concern | Countersign | Agent Inbox | gotoHuman |
|---|---|---|---|
| Primary model | LangGraph-first SDK and Agent Inbox-compatible payload | LangGraph HumanInterrupt / HumanResponse reference types | Hosted review requests tied to templates and webhooks |
| Review UI | Embeddable React primitives, styled inbox, action diff, validated edits, and audit timeline | Closest fit when retaining an existing Agent Inbox flow | Hosted inbox and configurable review UI |
| Workflow resume | Agent Inbox-compatible Command(resume=…) values; self-hosted and Platform adapters | Native LangGraph interrupt/resume | Review completion returned to a workflow or webhook |
| Controls | Policies, roles, quorum, amount thresholds, edit JSON Schema, and expiry rules | Controls supplied in the interrupt | Template fields, review controls, and hosted configuration |
| Audit focus | Request → decision → execution outcome, evidence export, hash-chain verification, and backup tools | Determined by the host application | Managed review history and response APIs |
| Deployment | Local evaluation API, Postgres team backend, and tested AWS blueprint; no public hosted deployment yet | Part of the LangGraph ecosystem | Managed hosted service |
Claims, bounded
Countersign does not yet claim a live managed deployment, live Slack/SES delivery, or a deployed EventBridge schedule. The implementation and contracts are tested locally; provider credentials and production operations remain deployment work.
Do not migrate a working Agent Inbox graph merely to rename its payload. The compatibility path keeps the interrupt shape and adds policy, provenance, audit, and deployment controls at the bridge.
Current sources
- LangGraph interrupt reference for the retained Agent Inbox types and their current deprecation status.
- gotoHuman overview, web UI guide, and request API.
- HumanLayer repository for its current open-source positioning and legacy SDK links.