Obsigno sits in front of your agents' MCP tool calls — enforcing policy before anything executes, then signing every decision into a chain where later modification is detectable.
Your agents read files, query production, send mail, move money — all through MCP tool calls. When something goes wrong, most teams can't prove what the agent actually did, and can't stop a dangerous call before it fires.
Today the agent's logs usually live where the agent can write. That isn't evidence — it's a suggestion.
One choke point sits between the agent and its tools. Enforcement is only unbypassable when the client cannot reach or launch the upstream server directly.
YAML/JSON rules, Cedar, or OPA are evaluated before forwarding. With a policy configured, unmatched calls deny by default. Denied calls never reach the upstream server.
Every decision — allow and deny — is appended to a hash-chained, Ed25519-signed ledger. Payloads are hashed, not stored, so you prove what happened without leaking secrets.
Integrity is verifiable with the public key alone. Auditors prove the record is intact — without any power to change it.
Agents rarely stop at one tool. Obsigno signs the same trace ID across every MCP server a task touches, so related actions can be verified together. Today, task-level correlation requires the client or orchestrator to propagate that trace ID across calls. Without propagation, Obsigno generates a per-call ID.
Signed tool-call evidence can support record-keeping and control programs, including EU AI Act, SOC 2, and ISO/IEC 42001 work. Obsigno does not make a system compliant by itself; applicability and retention requirements depend on the deployment.
Put Obsigno in front of your existing server command — the audit trail and policy gate come for free.
Start on stdio in five minutes. Bring the audit your agents don't have yet.