---
title: "Get Flywheel Run Diff Route"
method: GET
path: "/api/v1/flywheel-runs/{flywheel_run_id}/diff"
tags: ["flywheel"]
---

# Get Flywheel Run Diff Route

`GET /api/v1/flywheel-runs/{flywheel_run_id}/diff`

V2.8 — structured diff for a historical FlywheelRun.

Computes diff between ``source_version_id`` and ``promoted_version_id``
on the run.  Returns ``has_changes=false`` for dismissed runs (no
promoted version) or legacy rows with null version IDs.

## Path parameters

- `flywheel_run_id` string, uuid, required

## Response `200`

Successful Response

- RunDiffResponse — V2.2 — Structured diff between a prod agent's active version and its candidate version. Drives the Changes tab.
  - `has_changes` boolean, required
  - `candidate_version_id` string, uuid, nullable
  - `prod_version_id` string, uuid, required
  - `prompt_diff` PromptDiffSection — System-prompt diff between the candidate and prod versions.
    - `old` string, required
    - `new` string, required
  - `scenario_diffs` ScenarioDiffEntry[]
    - `scenario_id` string, required
    - `name` string, required
    - `change_type` 'added' | 'modified' | 'removed', required
    - `old` object, nullable
    - `new` object, nullable
  - `settings_diffs` SettingsDiffEntry[]
    - `field` string, required
    - `old` unknown
    - `new` unknown
  - `tools_diffs` ToolsDiffEntry[]
    - `tool_id` string, required
    - `name` string, required
    - `change_type` 'added' | 'modified' | 'removed', required
    - `old` object, nullable
    - `new` object, nullable
  - `knowledge_diffs` KnowledgeDiffEntry[]
    - `kb_id` string, required
    - `name` string, required
    - `change_type` 'added' | 'modified' | 'removed', required
    - `old` object, nullable
    - `new` object, nullable
  - `candidate_kb_scenarios` object[]
  - `candidate_tool_scenarios` object[]
  - `candidate_full_settings` object, nullable
  - `candidate_system_prompt` string, nullable
  - `label` string, nullable

## Other responses

- `404` — Not Found
- `422` — Validation Error

---

[API](https://skmtc.dev/getanana/apis/cleon-api.md) · [All operations](https://skmtc.dev/getanana/apis/cleon-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/getanana/cleon-api/revisions/c0f54348e251/schema)