XCP

Architecture & Evidence

A constrained runtime built to prove what happened.

Deterministic projects, authenticated execution and machine-verifiable evidence across PC and Xbox.

Overview

From an editable file to a measured frame.

  1. Person / IDE / AI agent
  2. Editable XCP project
  3. Deterministic builder
  4. Local validation + host profile
  5. Authenticated PC–Xbox transport
  6. Content-addressed project store
  7. XCP Creative Host
  8. 2D / 3D / UI / audio / behavior / XVM
  9. Observation / capture / receipt / rollback

Foundations

What the runtime is made of.

These are not features layered onto a general-purpose host. Each one exists because a specific class of unverifiable outcome had to be made impossible.

Deterministic project and bundle contracts

Identical source emits an identical canonical manifest and content digest. Malformed paths, duplicate identities, dependency cycles, symlinks and tampering all fail closed.

Authenticated worker transport

One authenticated PC-to-Xbox channel with ephemeral session material. No credential is persisted on the console.

Content-addressed installation

Bundles are stored by digest and shared blobs are reference-counted, so an install is immutable and a reap cannot remove something still referenced.

Atomic activation

Exactly one version is current. Activation is an append-only, hash-chained journal with exact preconditions and replayable transitions.

Exact rollback

The previous version is restored, not rebuilt. A rejected candidate cannot disturb the version that is working.

Structured errors

Every failure carries a stable machine code plus complete details. Callers branch on the code, never on message text.

Correction ledgers

Append-only and hash-chained: what failed, what was changed in response, and whether the change worked.

Graph Runtime as control plane

Admission freezes selection, plan and module identity before execution begins, so what ran is knowable afterwards.

XVM as compute plane

A bounded integer virtual machine with a 26-opcode instruction set, structured control flow and a static fuel proof. Work that cannot be shown to terminate within budget is refused before it runs.

CPU canonical verification

The CPU reference interpreter defines the correct answer and is the universal fallback.

GPU through measured gates only

A GPU result becomes authoritative only on exact byte agreement with the reference. On divergence the runtime falls back rather than choosing a winner.

D3D11 and measured public-UWP D3D12

The foreground surface and the compute surface are both measured within public-UWP limits. No client-supplied shader is compiled on the device.

Private application storage

Projects, bundles and evidence live in app-private storage with a characterized capacity, committed and reclaimed in full.

Reproducible evidence

Reports are byte-identified. A claim on this site points at a report with a length and a digest, not at a description of one.

Performance figures appear further down as proof that this foundation is substantial. They are not the purpose of the product.

Evidence hierarchy

Eight layers, from a sentence to a digest.

A reader should be able to stop at the layer that satisfies them and keep descending if it does not.

  1. 1Human-readable summaryWhat was attempted and what happened.
  2. 2Machine-readable verdictA decision field a tool can branch on: pass, ready, not ready.
  3. 3Project and bundle identityThe exact digests the run was performed against.
  4. 4Runtime and package identityThe signed worker and its full package family name.
  5. 5Observations and capturesCounters, logs and deterministic frames with their own digests.
  6. 6Correction ledgerThe failures, the corrections and their order.
  7. 7Exact update and rollback proofThe version chain, restored rather than rebuilt.
  8. 8Full hashes and report referencesByte lengths and SHA-256 digests, printed in full.

Measurements

What has been measured, and where.

Every figure below is bound to a report in the programme repository. Local means implemented and tested on PC; measured on Xbox means driven live on retail hardware.

Creation, from zero, by an agent with no repository access

State
Measured on Xbox
Lifecycle operations
28 / 28 aggregate, across one interactive game and one utility
Blocker assertions
12 / 12
Captures
6 / 6
Confirmed ledger corrections
6 / 6
Final state
7 / 7 — one active base and one rollback target per project
Agent isolation
Zero repository files or metadata read, no samples, no internet, no credentials, no live access
Real correction chain
xcp.creative.module_capability_not_requested, xcp.creative.local_state_invalid, missing foreground surface, immutable-version collision, rollback-incompatible state
Final report
8,956 bytes · decision pass
Report digest
67b720e8e01b53ac772472637f71c8198783c47e3ab44d3e751cde516f48390c

Adaptation of a real external source

State
Measured on Xbox
Source
Minilens v1.2 — a Godot 2 project, GPL-3.0-or-later, used as an adaptation subject and not an XCP product
Exact upstream revision
fd38f0983f9115ac9fe7a7314604fdeee61e9f09
Generated project
320aea1c27487447854275661d239dea9fcb2aa3875bba2ef7bf58aab3d532ec
Deterministic bundle
72127a197fa2ccd8d9e12a5655badc0739d7510b6bf922bba62b7eb382bfa2ac
Lifecycle operations
14 / 14
Semantic acceptance
5 / 5
Readiness decision
ready_playable_with_degradation
Declared degradations
Authorized Ogg audio requires bounded PC-side PCM WAV transcoding; unsupported application/octet-stream media requires PC-side replacement or conversion
Live receipt
4,390 bytes · dcc9b9e07e1c293fed32fef0823321bf114237206ce8104994a0ed5f4262c2f3
Correction ledger
3,837 bytes · 8e47efd221d51485f4cb13fb4c36418d6522f406ea75cfb55b79098d7929d1e8
Open gate

The run above is exact and stands. Source fidelity is nonetheless a reopened, fail-closed gate: the achieved adaptation level is a behavioural subset of the original, not an equivalence claim. Work on higher fidelity is in progress and is deliberately not described here until it is validated in the authoritative repository state.

Evolution across a later authorized revision

State
Measured on Xbox
From revision
fd38f0983f9115ac9fe7a7314604fdeee61e9f09
To revision
1a8907dee324b532f0409aa6c3060525911e68e5
Real source diff
18 added · 88 modified · 4 removed · 84 unchanged files
Semantic elements
18 added · 108 modified · 5 removed · 70 unchanged
Output materialization
50 reused · 12 rebuilt · 2 overlays applied · 2 removed
Emitted project
immutable 1.1.0 · 0e0e835c10f06e4c49aa5f903786719f2193d4aacdfed1db253aaac10ce45e18
Lifecycle
14 / 14 operations, 5 / 5 assertions, 3 / 3 captures
Version chain
exact 1.0.0 → 1.1.0 → 1.0.0 update and rollback
Receipt
4cd8cc500ff64709cc964f3e7af1ed0bd60dbb715fa8afd70756a2c33ac97eb4
Ledger
89a6ee93078abd35b21d6f945cb8cd655474010202f40959b74b98ea7493c116
Final report
3,890 bytes · e8ffd39f93b254291418add52c3d40f7749c47462e56ec9bc33cef4b668f74d8

Creative host, restored exactly after a fresh session

State
Measured on Xbox
Projects
Three public projects installed, launched, observed and captured
Fresh-session restore
Exact signal-garden@1.0.0 restored; a binding that is not exact fails closed
Observation after restore
Pulse, XVM-invocation and audio-cue counts equal at 34,889
Violations
0
Evidence report
65,537 bytes · c24b2334fd54b316e9fcdad3332d61270990ff24704cac8358068e521e72eb1a

Studio, validated outside the development repository

State
Measured local
Persistent shell
Dedicated Home, Create, Project, Adapt, Evolve, Playtest, Device and Evidence pages over the existing lifecycle adapters
Portable toolchain
PC-side kit 1.8.0, 73 files, manifest-bound
Manifest digest
86d2cefebd9e01d69e3eb7bd15c17b70a7a501decdcb6f0fbef109515ed46346
External run
Release app and kit copied outside the repository, PYTHONPATH removed; created and opened a project, completed a lifecycle prepare, a real adaptation and an evolution
Repository suite
828 / 828
C# suite
21 / 21 in Debug and Release
Studio Python
31 / 31
Evidence hygiene
29 / 29
Xbox impact
None. No worker build, package, deploy or live state mutation was required.

Identities

The exact package the console was running.

Evidence without a package identity is a description of an event, not a record of one.

Promoted creative worker
0.1.166.0
Signed package length
1,789,690 bytes
Package digest
1cb76af32b62f6edba60071f6fa0cbedeb87a0696123de67665a35baa86e5527
Deployed family name
XComputeProbe.WorkerPrototype_0.1.166.0_x64__d8ha3mrf4bp1p
Preserved baselines
.165 C3-complete · .164 regression and tamper-negative · .162 agent-native
Non-promotable
.163 remains an immutable path-length diagnostic and is never promoted

Correction ledgers

A ledger is append-only and hash-chained, written while the work runs. It records the structured failure, the correction derived from it and whether the retry succeeded — so a claim that something was fixed can be checked against the sequence that fixed it, rather than trusted.

Measured platform envelope

Hardware
Retail Xbox Series X in Developer Mode
Application memory limit
5,368,709,120 bytes — 5.0 GiB, as reported to a packaged command on the console
App-private storage
32,212,242,432 bytes characterized, committed and reclaimed in full
D3D12 FP32, calibrated
4,632.654 GFLOP/s
D3D12 FP32, soak
7,705.76 GFLOP/s

These are measured workload results on a public-UWP surface. They are not a full-console figure and no full-console claim is made anywhere in this programme.

Runtime boundaries

Constrained by design.

These constraints are enforced in the runtime and checked by a capability scan before any package is signed. They are the reason the measurements above are worth reading.

No jailbreak or firmware modificationPublic UWP
No arbitrary EXE or DLL uploadBefore transport
No shell or process spawningIn the runtime
No full trustIn the manifest
No broad filesystem accessApp-private only
No native or host JITIn the runtime
No client-supplied runtime shadersAt admission
No credential persistence on XboxEphemeral session
No restricted-capability driftScanned before signing
No unmeasured GDK or full-console claimIn the evidence

FAQ

Four questions worth answering directly.

Does XCP jailbreak or modify the console?
No. XCP operates within measured Xbox Developer Mode and public-UWP boundaries. It does not modify firmware, bypass the platform security model or upload arbitrary native code.
Does the AI model run on the Xbox?
No. Reasoning, creation, adaptation and correction happen on the PC side. Xbox executes bounded, validated artifacts through the measured XCP runtime, and the console stores no model-provider credentials. A model provider may itself be remote.
Is XCP an alternative to publishing a game on Xbox?
No. XCP is a development and verification platform that runs on retail Xbox Series hardware in Developer Mode. It is not a consumer distribution route and does not replace retail publishing.
Can XCP run any existing game?
No. Adaptation reconciles a source project against the measured host profile, and every element receives one explicit disposition. Work that cannot cross is reported as degraded, unsupported or requiring human intervention rather than silently dropped.

Current claim boundary

What this programme does and does not assert today.

XCP Studio runs on Windows only — for now. It is a WinUI 3 desktop application; the console side is unaffected.

  • XCP operates on real retail Xbox Series hardware through Developer Mode.
  • It is not a consumer publishing replacement.
  • AI reasoning is normally PC-side; the console executes validated artifacts.
  • The Studio has been validated outside the development repository.
  • No public installer exists, and none is claimed.
  • Source-fidelity work beyond the measured behavioural subset is in progress and is not claimed here until it is committed and validated in the authoritative repository state.
Inside XCP Studio Availability