Runs in your browser on a fixture from the NovaFabric repository. It reads files; it does not talk to a running server. The real interface is the CLI.

capsule.yaml1,362 bytes

schema_version: "0.1.0"
novafabric_version: "0.6.12"
run_id: "01KR5SQZPDGTKE3MDP3ZRX8WP1"
created_at: "2026-04-15T10:00:00+00:00"
finished_at: "2026-04-15T10:00:04+00:00"
duration_ms: 4127
command:
  - "python"
  - "review.py"
  - "--diff"
  - "examples/sample.diff"
exit_code: 0
status: "success"
capture_mode: "cli-wrapper"
working_directory: "~/projects/code-review-agent"
host:
  arch: "x86_64"
  os: "linux"
  python: "3.12.4"
  cpu_count: 16
  memory_bytes: 67108864000
  gpu: []
  hostname_redacted: true
trace_ref: "trace.jsonl"
trace_root_span_id: "0123456789abcdef"
model_calls_ref: "model-calls.jsonl"
tool_calls_ref: "tool-calls.jsonl"
assets_ref: "assets.jsonl"
environment_ref: "env.lock"
replay_policy_ref: "replay.yaml"
redaction_proof_ref: "redaction-proof.json"
lineage_ref: "lineage.jsonl"
model_call_count: 2
tool_call_count: 2
mutating_tool_count: 0
inputs:
  -
    name: "diff"
    path: "inputs/sample.diff"
    content_hash: "sha256:2a8439e85cae440ff7e28be7009b7056ccff0597d706a093a7e0c44e90f022b7"
    size_bytes: 1240
    media_type: "text/x-diff"
outputs:
  -
    name: "review"
    path: "outputs/review.md"
    content_hash: "sha256:5d93970a885c44d5babc3cf3dabcbcbd275e1c3df1fdd020f76126bc14bf5819"
    size_bytes: 612
    media_type: "text/markdown"
metadata:
  agent: "code-review-agent@0.1.0"
  prompt: "code-review-prompt@0.1.0"

A full capture also writes env.lock, redaction-proof.json, replay.yaml, lineage.jsonl and the run's inputs and outputs; this fixture keeps the four shown here. Every file, one by one →

Check the manifest against the schema

The manifest above, as JSON, validated against the run-capsule JSON Schema that an installed CLI uses. Break it on purpose: the check has to turn red.

TRY TO BREAK IT

invalid — undefined errors

{
  "schema_version": "0.1.0",
  "novafabric_version": "0.6.12",
  "run_id": "01KR5SQZPDGTKE3MDP3ZRX8WP1",
  "created_at": "2026-04-15T10:00:00+00:00",
  "finished_at": "2026-04-15T10:00:04+00:00",
  "duration_ms": 4127,
  "command": [
    "python",
    "review.py",
    "--diff",
    "examples/sample.diff"
  ],
  "exit_code": 0,
  "status": "success",
  "capture_mode": "cli-wrapper",
  "working_directory": "~/projects/code-review-agent",
  "host": {
    "arch": "x86_64",
    "os": "linux",
    "python": "3.12.4",
    "cpu_count": 16,
    "memory_bytes": 67108864000,
    "gpu": [],
    "hostname_redacted": true
  },
  "trace_ref": "trace.jsonl",
  "trace_root_span_id": "0123456789abcdef",
  "model_calls_ref": "model-calls.jsonl",
  "tool_calls_ref": "tool-calls.jsonl",
  "assets_ref": "assets.jsonl",
  "environment_ref": "env.lock",
  "replay_policy_ref": "replay.yaml",
  "redaction_proof_ref": "redaction-proof.json",
  "lineage_ref": "lineage.jsonl",
  "model_call_count": 2,
  "tool_call_count": 2,
  "mutating_tool_count": 0,
  "inputs": [
    {
      "name": "diff",
      "path": "inputs/sample.diff",
      "content_hash": "sha256:2a8439e85cae440ff7e28be7009b7056ccff0597d706a093a7e0c44e90f022b7",
      "size_bytes": 1240,
      "media_type": "text/x-diff"
    }
  ],
  "outputs": [
    {
      "name": "review",
      "path": "outputs/review.md",
      "content_hash": "sha256:5d93970a885c44d5babc3cf3dabcbcbd275e1c3df1fdd020f76126bc14bf5819",
      "size_bytes": 612,
      "media_type": "text/markdown"
    }
  ],
  "metadata": {
    "agent": "code-review-agent@0.1.0",
    "prompt": "code-review-prompt@0.1.0"
  }
}

On your machine

nova — bash

$ nova capture python review.py --diff examples/sample.diff
$ nova validate <run-id>
$ nova replay <run-id> --mode forensic

Inside a Run Capsule

Check the manifest against the schema

On your machine