Continuum

When an enterprise agent fails, its verified obligations move safely to a fenced successor - and the outcome is independently proven.

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The agent failed. The promise did not.

Enterprise agents increasingly own long-running obligations: onboard a compliant supplier, renew a contract, file a control report, or complete a regulated handoff. When an agent silently fails, ordinary retry logic can lose the obligation, reuse revoked memory, overlap authority, repeat an external effect, or claim success from its own logs.

Continuum is a governed succession layer for autonomous enterprise agents. It detects missing evidence, selects a deployment-backed successor with Gemini, transfers only authorized context, completes the obligation once under the demonstrated gateway/provider failure model, and has a separate verifier prove the result.

One coherent workflow

Continuum records a €250,000 supplier-onboarding obligation and its required compliance evidence. A persisted Cloud Tasks deadline expires. No failure event exists; the required evidence is simply absent. Pub/Sub deliberately redelivers that missing-event signal after the first delivery fails. A Firestore-backed cross-department fleet catalog resumes after a simulated 21-day dormancy. A deterministic gate evaluates immutable v18, v19, and v20 publications for health, capability, jurisdiction, contract compatibility, scope, and trust. Google ADK invokes Gemini 3.6 Flash on Vertex AI. Gemini must cite the incident and deployment evidence and choose only from the eligible set. In the accepted run it selected warm v19 by explicitly trading 18-second recovery against very-high assurance; this is not a max-score shortcut. Deterministic policy validates the recommendation, fences v17 at the new authority epoch, and activates v19. Google Model Armor stops a raw prompt-injection attack before Gemini. Continuum then reconstructs minimum context: two verified facts cross; a predecessor secret, unsupported model inference, and revoked memory do not. The v19 action gateway checks workload identity, authority epoch, policy, explicitly labelled external-evidence availability and freshness, context receipt, request digest, and idempotency in one Firestore transaction. Two Pub/Sub deliveries produce one reconciled, reversible synthetic GitHub work item—Issue #41—not two Firestore stand-ins. A separately deployed read-only verifier recomputes the evidence, directly reads authority/compliance/provider state, and alone issues artifact six: VERIFIED, FAILED, or INCONCLUSIVE.

Why it is agentic

Gemini is causally useful without becoming an authority boundary. Its evidence-cited successor choice changes which eligible workload is activated. It cannot mint authority, execute an action, admit an ineligible candidate, or attest its own success. Unsupported or uncited output fails closed.

Verified Resilience Brief

Only after the independent verifier issues VERIFIED, Continuum reduces the accepted bundle to five bounded facts. Gemma 4 creates a strictly cited resilience plan; deterministic admission then permits Veo 3.1 Lite and Lyria 3 to render content-addressed post-incident training media. The outputs are marked DERIVED_NOT_AUTHORITY_OR_EVIDENCE and can never select a successor, grant authority, execute an effect, or attest the incident.

The exact managed-model receipt and judge-accessible generated assets are checksum-pinned at:

https://github.com/milos-plavsic/continuum/releases/tag/multimodal-proof-8bec862

Architecture and production discipline

The Google Cloud reference binding uses five private Cloud Run services with distinct user-managed workload identities: control, predecessor v17, successor v18, warm successor v19, and independent verifier. Firestore provides transactional events, projections, outbox, authority fencing, and idempotency. Cloud Tasks owns the real deadline. Pub/Sub supplies at-least-once delivery. OpenTelemetry exports the complete lifecycle to Cloud Trace.

The portable Continuity Contract exports five content-addressed pre-attestation artifacts—obligation, authority grant, succession manifest, revocation proof, and execution receipt. Only the independent verifier may issue the sixth continuity attestation. A cloud-neutral three-call SDK, credential-free local consumer, and first-party workflow-engine companion bridge demonstrate that adopting the contract does not require replacing a domain model, scheduler, retry policy, or DLQ with Google Cloud.

Verifiable proof

The exact application release is d4d7d52e56c3d3c123a708a279be6bda7189e647, bound to one immutable Google-signed image across five Cloud Run revisions. Fresh run judge-final-d4d7d52-20260827T223700Z produced all 17 mandatory evidence objects and 174 correlated Cloud Trace spans, including real ADK + Vertex AI Gemini 3.6 Flash calls, Model Armor MATCH_FOUND, Pub/Sub redelivery, one reversible GitHub work item, stale-agent denials, a deterministic-baseline deviation receipt, and verifier attestation. GLEIF was LIVE. VIES reported MS_UNAVAILABLE, so Continuum transparently used a still-fresh CACHED_WITHIN_POLICY observation whose source evidence and prior independent attestation are bound in Firestore. The offline semantic verifier returned PASS without network access or credentials; it proves archive integrity and semantic consistency, not capture provenance or upstream factual truth.

The complete security-audited packet is publicly downloadable and checksum pinned:

https://github.com/milos-plavsic/continuum/releases/tag/cloud-proof-d4d7d52

Archive SHA-256: 14d2005d1a1360528e2ae84ad72c485ff92963a5ecd9e48121cd56edf790d3f6

Public build write-up and social proof

Technical article created for entering this hackathon: https://dev.to/milos-plavsic/the-agent-failed-the-promise-did-not-building-verifiable-agent-succession-oe4

LinkedIn build post with #AllThingsAgenticHackathon: https://www.linkedin.com/feed/update/urn:li:share:7498513309642616832/

Hosted judge surface

A public, presentation-only Cloud Run showcase makes the product path and credential-free evidence immediately inspectable:

https://continuum-showcase-rdzvxiysbq-ew.a.run.app

It is independently deployed under a dedicated service identity with no project-level role and exposes no mutation, OpenAPI, control-plane, Firestore, Pub/Sub, Vertex AI, agent, or verifier route. The five effect-bearing canonical services remain private.

Data sources

The canonical run uses synthetic procurement and compliance records, immutable successor deployment records, Firestore lifecycle/authority/idempotency evidence, Cloud Tasks deadline metadata, Pub/Sub delivery identity, ADK/Gemini request-response metadata, Cloud Run revision identities, and correlated Cloud Trace spans read from owning APIs. It ingests no personal data, confidential enterprise records, or third-party procurement system.

Findings and learnings

Persistence is not continuity: durable state can still preserve stale authority, poisoned context, or a duplicated effect. The useful boundary is a portable contract separating obligation, model recommendation, deterministic authority, execution receipt, and independent verdict. Real cloud runs also exposed wire canonicalization, context-receipt, and trace-correlation defects that failed closed and became regression tests before the accepted run.

Reproducibility

Run ./scripts/quality-gate.sh from a clean checkout. The protected GitHub workflow executes 215 tests, enforces genuine 100.0% statement and branch coverage with no source exclusions, runs C0–C6 conformance and the release gate, audits generated state and credentials, and builds the submitted non-root container image.

Public auditability

The exact downloaded main-CI quality packet is permanently published at https://github.com/milos-plavsic/continuum/releases/tag/quality-proof-12e116b. It contains XML, detailed JSON, browsable HTML, exact source/measured inventories for all 39 modules, 215-test discovery, and nested checksums verified after download: 4,152/4,152 statements and 1,154/1,154 branches. The unsuccessful canonical attempts and the functional PR lineage behind the final release pin remain public at https://github.com/milos-plavsic/continuum/blob/main/docs/FAILURE_LEDGER.md. Coverage is execution evidence, not by itself proof of semantic correctness.

Scope and limitations

The live provider effect is a reversible synthetic GitHub Issues work item, independently reconciled by the verifier; it is not a production procurement-system integration. The machine-readable trust profile explicitly caps the claim at internal content integrity and semantic consistency: it does not prove capture provenance, upstream truth, an uncompromised cloud/model, or Byzantine assurance. The project proves one regional Google Cloud reference binding, not universal exactly-once execution, global credential revocation, Byzantine consensus, or third-party interoperability. Continuity Contract 0.1-draft is a protocol proposal, not an adopted standard.

Continuum was created as a new implementation during the All Things Agentic Hackathon submission period. No source was copied from prior projects or unmerged external-contributor pull requests; provenance is documented in the repository.

Built With

  • cloud-run
  • cloud-storage
  • cloud-tasks
  • cloud-trace
  • ed25519
  • fastapi
  • firestore
  • gemini-3.6-flash
  • gemma-4
  • google-adk
  • lyria-3
  • opentelemetry
  • pub/sub
  • pydantic
  • python
  • veo-3.1
  • vertex-ai
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