Tenancy Stamping

For multi-tenant deployments, every Forge audit event can carry top-level org_id and workspace_id keys so SIEM / audit-warehouse consumers filter by tenancy without joining against auth_verify rows. See issue #157.

Two layers

The same agent process supports both the static-deployment case (one agent serves one workspace) and the multi-tenant routing case (one agent serves many workspaces, the orchestrator picks per request).

Tenancy fields (`org_id` / `workspace_id`)

Layer	Source	Wins when
1 — Explicit on event	`AuditEvent.OrgID` / `AuditEvent.WorkspaceID` set before emit	Always — caller-owned event takes precedence over every fallback
2 — Per-request override	`X-Forge-Org-ID` / `X-Forge-Workspace-ID` request headers	Inside the request scope when present; ctx falls through to layer 3 otherwise
3 — Deployment-time stamp	`FORGE_ORG_ID` / `FORGE_WORKSPACE_ID` env vars	Whenever the higher layers carry no value

Each field is resolved independently. A request that overrides only X-Forge-Org-ID still lets the env stamp fill in workspace_id.

Entity fields (`entity_id` / `entity_type`) — #164

Layer	Source	Wins when
1 — Explicit on event	`AuditEvent.EntityID` / `AuditEvent.EntityType` set before emit	Always — caller-owned event takes precedence
2 — Deployment-time stamp	`FORGE_AGENT_ID` env / forge.yaml `agent_id` → `entity_id`; `entity_type` hardcoded to `"agent"`	Whenever the higher layer is empty

Entity identity has no per-request header layer — entity is fixed at process startup. If a deployment needs per-request entity routing, the tenancy layer above already covers that (an agent serving multiple workspaces). Agent identity is the process, by definition.

entity_type and entity_id match the field names + values the guardrails library uses (see EntityType constants: agent / workflow / assistant). Forge only runs agents today, so the value is always "agent"; future entity types are an additive value change, not a schema change.

Static tenancy (one agent per workspace)

The simplest case: deploy one Forge agent into one workspace, declare the tenancy via env, never set headers. Every emitted event — including startup banners — carries the stamp.

# Kubernetes deployment fragment
env:
  - name: FORGE_ORG_ID
    value: "org_abc123"
  - name: FORGE_WORKSPACE_ID
    value: "ws_xyz789"

The audit stream then looks like:

{"ts":"2026-06-14T10:00:00Z","event":"agent_card_published","schema_version":"1.0","org_id":"org_abc123","workspace_id":"ws_xyz789","fields":{...}}
{"ts":"2026-06-14T10:00:05Z","event":"session_start","schema_version":"1.0","seq":1,"correlation_id":"...","task_id":"...","org_id":"org_abc123","workspace_id":"ws_xyz789"}
{"ts":"2026-06-14T10:00:08Z","event":"llm_call","schema_version":"1.0","seq":2,"correlation_id":"...","task_id":"...","model":"...","provider":"...","org_id":"org_abc123","workspace_id":"ws_xyz789"}

SIEM filter: org_id = "org_abc123" AND workspace_id = "ws_xyz789".

Per-request routing (one agent serves many workspaces)

For deployments where one Forge agent fronts many workspaces and the orchestrator routes per request, set the env vars to a default tenancy (or leave them empty) and have the orchestrator send the override headers on every request:

curl -X POST https://agent.example.com/ \
  -H 'X-Forge-Org-ID: org_def456' \
  -H 'X-Forge-Workspace-ID: ws_pqr012' \
  -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","id":"1","method":"tasks/send","params":{...}}'

Every audit event emitted during that request carries "org_id":"org_def456","workspace_id":"ws_pqr012". The next request from a different workspace gets its own stamp.

Startup banners (agent_card_published, policy_loaded, audit_export_status) still reflect the env stamp because they have no request context.

Outbound propagation (agent-to-agent flows)

When one Forge agent calls another (via the egress proxy with explicit propagation), the helper coreruntime.TenancyContextFromContext(ctx).ApplyToHTTPHeaders(req.Header) writes both headers onto the outbound request. The downstream agent picks them up at its A2A boundary the same way.

Auto-propagation is NOT built into the egress proxy. The agent only propagates tenancy when it knows the target is a tenancy-aware Forge peer. This mirrors the workflow-header behavior: explicit only, to avoid leaking tenancy to unrelated third-party APIs.

Outbound propagation (platform callouts)

Every Forge→platform HTTP callout — admission (FORGE_ADMISSION_URL), the remote session store, and the MCP platform token / authorize endpoints (type: platform / type: user) — sends Org-Id + Workspace-Id headers (from FORGE_ORG_ID / FORGE_WORKSPACE_ID) alongside Authorization: Bearer ${FORGE_PLATFORM_TOKEN}. This is a hard contract, not best-effort: the platform verifies a per-org HS256 token and needs Org-Id to select the signing secret before it can validate the bearer — omitting it returns 401 "missing org-id header". Note the header spelling here is Org-Id / Workspace-Id (the platform-callout convention), distinct from the inbound X-Forge-Org-ID / X-Forge-Workspace-ID request-override headers above.

Backwards compatibility

Both org_id and workspace_id use omitempty. Deployments that set neither env nor header keep emitting the pre-tenancy JSON shape verbatim. Consumers that ignore unknown keys continue to work unchanged. The audit schema version is not bumped — additive optional fields are schema-compatible per the documented policy.

Distinct from auth_verify.fields.org_id

The auth provider chain resolves an Identity.OrgID from the inbound bearer token (whatever the issuer claims) and stamps it on auth_verify.fields.org_id for back-compat. That value reflects the user's org from their identity token.

The top-level org_id documented here is the deployment's declared tenancy — the operator's explicit assertion of where this agent runs. The two can differ legitimately (federated identity, cross-tenant invocation) and downstream consumers should treat them as independent signals. Both can be present on the same auth_verify event.

Tenancy Stamping