An open standard for coding event sounds.

Any agentic IDE or terminal editor can implement the Coding Event Sound Pack Specification (CESP) to give developers audio feedback when tasks complete, errors occur, or input is needed.

Agentic coding tools (Claude Code, Cursor, Windsurf, Copilot) run tasks in the background. You tab away, lose focus, and waste time waiting for something that finished 5 minutes ago. Sound notifications fix this — but every tool reinvents the wheel with its own format.

CESP standardizes the format so sound packs work everywhere. The concept — born in PeonPing — inspired Microsoft to add native sound hooks to VS Code for 50M+ users.

CESP v1.0 Specification defines:

• 9 event categories (session.start, task.complete, input.required, etc.) that any IDE maps to
• Manifest format (openpeon.json) with author info, checksums, licensing
• Directory structure and audio file constraints
• IDE mapping contract — each tool maps its own events to CESP categories

1. Create a directory with your sounds:

my-pack/
  openpeon.json
  sounds/
    Hello.mp3
    Done.mp3
    Error.mp3

2. Write a manifest (openpeon.json):

{
  "cesp_version": "1.0",
  "name": "my-pack",
  "display_name": "My Sound Pack",
  "version": "1.0.0",
  "categories": {
    "session.start": {
      "sounds": [
        { "file": "sounds/Hello.mp3", "label": "Hello!" }
      ]
    },
    "task.complete": {
      "sounds": [
        { "file": "sounds/Done.mp3", "label": "All done." }
      ]
    },
    "task.error": {
      "sounds": [
        { "file": "sounds/Error.mp3", "label": "Something went wrong." }
      ]
    }
  }
}

3. Validate against the schema:

python3 -c "
import json, jsonschema
schema = json.load(open('spec/openpeon.schema.json'))
manifest = json.load(open('my-pack/openpeon.json'))
jsonschema.validate(manifest, schema)
print('Valid!')
"

That's it. Your pack works with any CESP-compatible player.

Want to add CESP sound pack support to your CLI or coding tool? Copy the contents of INTEGRATE.md into your AI coding agent and let it handle the wiring.

You can also find it rendered at openpeon.com/integrate.

See the full spec for details on sound selection, volume control, and pack management.

• Orc Peon (Warcraft III) — the original peon-ping pack
• GLaDOS (Portal) — passive-aggressive AI companion

All official packs live in PeonPing/og-packs.

The OpenPeon registry is live at PeonPing/registry. The registry index is published to peonping.github.io/registry/index.json and currently lists 100+ packs.

Packs are hosted in their own repos. Official packs are in PeonPing/og-packs. Community packs live in contributor repos. See Registry Design for the architecture details.

The openpeon.com website lets you browse all registered packs with audio previews, filterable by tag, language, and trust tier (official/community). It also includes an integration guide for adding CESP support to any CLI. Source is in site/.

spec/
  cesp-v1.md                   # The specification
  openpeon.schema.json          # JSON Schema for manifests
  registry-entry.schema.json    # JSON Schema for registry entries
examples/                        # Example sound packs (peon, glados)
scripts/
  generate-registry.ts          # Registry generation script
site/                            # The openpeon.com website
docs/
  registry-design.md            # Registry architecture blueprint
tests/                           # Schema validation tests
CLAUDE.md                        # Project documentation for AI assistants
CONTRIBUTING.md                  # Contribution guide

MIT