# AGENTS.md — Build guide for ScreenFlow

## Project scope
Record a selected Mac display/window and optional microphone with visible controls, trim non-destructively and add a small set of callouts. Export through AVFoundation with an explicit format and recoverable job state.

Catalogue verdict: yes. ScreenFlow's solo core is compact: build a local Mac screen recording + editing workflow that imports user-owned media, applies the core edit or transformation, previews it, and exports a standard file. A competent builder can reach a useful personal version in one sitting, while the paid product mainly wins on media pipeline, hosting, distribution.
Use the implementation prompt below to define the deliverable. Complete each phase's acceptance checks before extending the scope.

## Working agreement
- Inspect the repository and its existing instructions before choosing paths, dependencies or commands. Keep one coherent stack and explain changes to the proposed architecture.
- Plan a vertical slice that accepts a real input and produces the useful output described below. Persist only the state the prompt calls for; respect memory-only and upstream-managed workflows. Use fixtures only when they are clearly labelled.
- After scaffolding, document the actual install, development, check and build commands in README and keep them synchronized with the package or project manifest. Do not report commands as successful unless they ran.
- Work in small steps. At handoff, list implemented flows, checks actually performed, remaining blockers, and any credentials or provider setup the owner must supply.
- Do not publish, spend money, contact customers, delete source data or run irreversible migrations without the project owner's authorization.

## Prerequisites
- macOS, Xcode and a selected deployment target. Ask for each OS permission only when its feature is enabled; code signing and distribution are separate release tasks.
- Implementation components: Swift, SwiftUI and focused AppKit integrations for a macOS utility. SQLite or Codable files for local settings and history; macOS Keychain for credentials. ScreenCaptureKit and AVFoundation for capture, composition and export with timestamped source tracks.
- Scope boundary: production codecs, rendering speed, and media templates; hosted recording reliability

## Stack and architecture
- Swift, SwiftUI and focused AppKit integrations for a macOS utility.
- SQLite or Codable files for local settings and history; macOS Keychain for credentials.
- ScreenCaptureKit and AVFoundation for capture, composition and export with timestamped source tracks.
- Domain model: ScreenCaptureKit sessions, audio/video track timestamps, edit decisions, annotations and export jobs

## Security and data integrity
- Require explicit screen/window and microphone choices with OS permission, an always-visible recording state and an immediate stop control. Keep tracks local by default, define deletion/retention controls and never collect keystrokes or upload recordings without separate consent.
- Correctness boundary: Permission denial cannot create an empty success artifact; edit timing must respect the source tracks' timestamps rather than assuming a fixed frame rate.
- Keep UI state on the main actor, cancel obsolete background tasks, and avoid blocking system callbacks. Record only the selected feature scope, with clear retention controls.
- Export settings and explicitly selected history without secrets. Preserve the last working configuration and provide a reset that does not delete user source files.

## Agent implementation rules
- Project rule — data model: ScreenCaptureKit sessions, audio/video track timestamps, edit decisions, annotations and export jobs
- Project rule — preserve this invariant: Permission denial cannot create an empty success artifact; edit timing must respect the source tracks' timestamps rather than assuming a fixed frame rate.
- Project rule — acceptance evidence: Record a short fixture with an audible clap and retain A/V alignment after trimming; cancelling export leaves the source recording intact.

## Optional agent skills and references
- Optional external skill: [swiftui-expert-skill](https://github.com/AvdLee/SwiftUI-Agent-Skill/blob/main/skills/swiftui-expert-skill/SKILL.md) — Build and review native SwiftUI views, state management, navigation, accessibility and rendering performance. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission.
- Optional external skill: [swift-concurrency](https://github.com/AvdLee/Swift-Concurrency-Agent-Skill/blob/main/skills/swift-concurrency/SKILL.md) — Design Swift async tasks, actors, isolation, cancellation and safe data sharing, including Swift 6 migration. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission.
- Optional external skill: [sharp-edges](https://github.com/trailofbits/skills/blob/main/plugins/sharp-edges/skills/sharp-edges/SKILL.md) — Review security-sensitive APIs and configuration for dangerous defaults and easy-to-misuse interfaces. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission.

Read the linked SKILL.md and its dependencies before adding a skill. Select only the skills matching this project's runtime and task; their documentation does not supply API access, credentials or approval to perform external actions. Pin the reviewed revision where the tool supports it. Follow the chosen agent's documented project-level installation mechanism.

## Distribution ideas
These are optional planning notes. Obtain the owner's approval before publishing or contacting anyone.
- Demonstrate the actual ScreenFlow-inspired workflow with owned or clearly labeled sample data: Record a selected Mac display/window and optional microphone with visible controls, trim non-destructively and add a small set of callouts. Export through AVFoundation with an explicit format and recoverable job state.
- Publish a reproducible walkthrough with this observable result: Record a short fixture with an audible clap and retain A/V alignment after trimming; cancelling export leaves the source recording intact.
- Explain who can operate this scoped tool, its setup and ongoing costs, and these remaining product gaps: production codecs, rendering speed, and media templates; hosted recording reliability Avoid guaranteed savings, performance scores or implied endorsement.

## Engineering roadmap
1. Phase 1 — Scope and fixtures. Implement this bounded workflow: Record a selected Mac display/window and optional microphone with visible controls, trim non-destructively and add a small set of callouts. Export through AVFoundation with an explicit format and recoverable job state. Record prerequisites, select representative user-owned fixtures and document the unsupported features: production codecs, rendering speed, and media templates; hosted recording reliability
2. Phase 2 — Durable model. Model ScreenCaptureKit sessions, audio/video track timestamps, edit decisions, annotations and export jobs Add migrations or a versioned document format, explicit validation, stable IDs and a visible import-error report. Preserve this rule: Permission denial cannot create an empty success artifact; edit timing must respect the source tracks' timestamps rather than assuming a fixed frame rate.
3. Phase 3 — Complete the first useful path. Implement the workflow's input, review and output interface, with clear controls and explicit empty/error states. Keep UI state on the main actor, cancel obsolete background tasks, and avoid blocking system callbacks. Record only the selected feature scope, with clear retention controls.
4. Phase 4 — Permissions and integration failure. Require explicit screen/window and microphone choices with OS permission, an always-visible recording state and an immediate stop control. Keep tracks local by default, define deletion/retention controls and never collect keystrokes or upload recordings without separate consent. Request integration credentials and permissions only for the enabled feature; show a disconnected state instead of mock results.
5. Phase 5 — Portable handoff. Export settings and explicitly selected history without secrets. Preserve the last working configuration and provide a reset that does not delete user source files. Include setup, operating limits, fixture walkthrough and shutdown/restart instructions in the README.
6. Phase 6 — Acceptance scenarios. Record a short fixture with an audible clap and retain A/V alignment after trimming; cancelling export leaves the source recording intact. Repeat the workflow after restart and with a denied permission or unavailable dependency; show recoverable failure rather than a success placeholder.

## Paid-product capabilities outside this build
- production codecs, rendering speed, and media templates
- hosted recording reliability
- large-scale rendering
- distribution and podcast hosting
- professional codecs, effects, and collaboration

## Implementation prompt
WORKING SLICE
Record a selected Mac display/window and optional microphone with visible controls, trim non-destructively and add a small set of callouts. Export through AVFoundation with an explicit format and recoverable job state.

Build this scoped ScreenFlow-inspired workflow with a documented data model and visible failure states.

Architecture
- Swift, SwiftUI and focused AppKit integrations for a macOS utility.
- SQLite or Codable files for local settings and history; macOS Keychain for credentials.
- ScreenCaptureKit and AVFoundation for capture, composition and export with timestamped source tracks.

Prerequisites and limits
macOS, Xcode and a selected deployment target. Ask for each OS permission only when its feature is enabled; code signing and distribution are separate release tasks.
Outside this release: production codecs, rendering speed, and media templates; hosted recording reliability

Data model and correctness
ScreenCaptureKit sessions, audio/video track timestamps, edit decisions, annotations and export jobs
Invariant: Permission denial cannot create an empty success artifact; edit timing must respect the source tracks' timestamps rather than assuming a fixed frame rate.
Keep UI state on the main actor, cancel obsolete background tasks, and avoid blocking system callbacks. Record only the selected feature scope, with clear retention controls.

Security and privacy
Require explicit screen/window and microphone choices with OS permission, an always-visible recording state and an immediate stop control. Keep tracks local by default, define deletion/retention controls and never collect keystrokes or upload recordings without separate consent.

Recovery and export
Export settings and explicitly selected history without secrets. Preserve the last working configuration and provide a reset that does not delete user source files.

Implementation order
1. Phase 1 — Scope and fixtures. Implement this bounded workflow: Record a selected Mac display/window and optional microphone with visible controls, trim non-destructively and add a small set of callouts. Export through AVFoundation with an explicit format and recoverable job state. Record prerequisites, select representative user-owned fixtures and document the unsupported features: production codecs, rendering speed, and media templates; hosted recording reliability
2. Phase 2 — Durable model. Model ScreenCaptureKit sessions, audio/video track timestamps, edit decisions, annotations and export jobs Add migrations or a versioned document format, explicit validation, stable IDs and a visible import-error report. Preserve this rule: Permission denial cannot create an empty success artifact; edit timing must respect the source tracks' timestamps rather than assuming a fixed frame rate.
3. Phase 3 — Complete the first useful path. Implement the workflow's input, review and output interface, with clear controls and explicit empty/error states. Keep UI state on the main actor, cancel obsolete background tasks, and avoid blocking system callbacks. Record only the selected feature scope, with clear retention controls.
4. Phase 4 — Permissions and integration failure. Require explicit screen/window and microphone choices with OS permission, an always-visible recording state and an immediate stop control. Keep tracks local by default, define deletion/retention controls and never collect keystrokes or upload recordings without separate consent. Request integration credentials and permissions only for the enabled feature; show a disconnected state instead of mock results.
5. Phase 5 — Portable handoff. Export settings and explicitly selected history without secrets. Preserve the last working configuration and provide a reset that does not delete user source files. Include setup, operating limits, fixture walkthrough and shutdown/restart instructions in the README.
6. Phase 6 — Acceptance scenarios. Record a short fixture with an audible clap and retain A/V alignment after trimming; cancelling export leaves the source recording intact. Repeat the workflow after restart and with a denied permission or unavailable dependency; show recoverable failure rather than a success placeholder.

Acceptance
Record a short fixture with an audible clap and retain A/V alignment after trimming; cancelling export leaves the source recording intact.
Use real source data or clearly labeled fixtures. Explain unsupported input and provider failures; do not fabricate analytics, delivery receipts, accuracy claims or security guarantees.

Optional agent guidance
Optional external skill: [swiftui-expert-skill](https://github.com/AvdLee/SwiftUI-Agent-Skill/blob/main/skills/swiftui-expert-skill/SKILL.md) — Build and review native SwiftUI views, state management, navigation, accessibility and rendering performance. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission.
Optional external skill: [swift-concurrency](https://github.com/AvdLee/Swift-Concurrency-Agent-Skill/blob/main/skills/swift-concurrency/SKILL.md) — Design Swift async tasks, actors, isolation, cancellation and safe data sharing, including Swift 6 migration. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission.
Optional external skill: [sharp-edges](https://github.com/trailofbits/skills/blob/main/plugins/sharp-edges/skills/sharp-edges/SKILL.md) — Review security-sensitive APIs and configuration for dangerous defaults and easy-to-misuse interfaces. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission.
Project rule — data model: ScreenCaptureKit sessions, audio/video track timestamps, edit decisions, annotations and export jobs
Project rule — preserve this invariant: Permission denial cannot create an empty success artifact; edit timing must respect the source tracks' timestamps rather than assuming a fixed frame rate.
Project rule — acceptance evidence: Record a short fixture with an audible clap and retain A/V alignment after trimming; cancelling export leaves the source recording intact.

## Completion evidence
Demonstrate the prompt's acceptance scenarios against the scoped workflow. Include setup from a clean checkout and failure recovery. Check persistence across restart and export/restore only for the state the prompt says to store; for memory-only tools, confirm that temporary content is discarded as specified. Record actual results and remaining limitations. A detailed plan alone does not establish a working replacement.