attune/work-summary/2026-02-05-universal-agent-phase2.md

Universal Worker Agent — Phase 2: Runtime Auto-Detection Integration

Date: 2026-02-05

Overview

Implemented Phase 2 of the Universal Worker Agent plan (docs/plans/universal-worker-agent.md), which integrates the runtime auto-detection module (built in Phase 1) with the worker registration system. Agent workers now register with rich interpreter metadata — binary paths and versions — alongside the simple runtime name list used for backward compatibility.

Changes

1. crates/worker/src/runtime_detect.rs

• Added Serialize and Deserialize derives to DetectedRuntime so detection results can be stored as JSON in worker capabilities.

2. crates/worker/src/registration.rs

• Added use crate::runtime_detect::DetectedRuntime import.
• set_detected_runtimes(runtimes: Vec<DetectedRuntime>) — Stores interpreter metadata under the detected_interpreters capability key as a structured JSON array (each entry has name, path, version). This supplements the existing runtimes string list for backward compatibility.
• set_agent_mode(is_agent: bool) — Sets an agent_mode boolean capability so the system can distinguish agent-mode workers from standard workers.

3. crates/worker/src/service.rs

• Added detected_runtimes: Option<Vec<DetectedRuntime>> field to WorkerService (defaults to None).
• with_detected_runtimes(self, runtimes) -> Self — Builder method to pass agent-detected runtimes into the service. No-op for standard attune-worker.
• Updated start() to call set_detected_runtimes() + set_agent_mode(true) on the registration before register() when detected runtimes are present.

4. crates/worker/src/agent_main.rs

• Added agent_detected_runtimes: Option<Vec<DetectedRuntime>> variable to stash detection results.
• After auto-detection runs, the detected runtimes are saved (previously they were consumed by the env var setup and discarded).
• After WorkerService::new(), chains .with_detected_runtimes(detected) to pass the metadata through.

5. crates/worker/src/lib.rs

• Re-exported DetectedRuntime from runtime_detect module for external use.

Worker Capabilities (Agent Mode)

When an attune-agent registers, its capabilities JSON now includes:

{
  "runtimes": ["shell", "python", "node"],
  "detected_interpreters": [
    {"name": "shell", "path": "/bin/bash", "version": "5.2.15"},
    {"name": "python", "path": "/usr/bin/python3", "version": "3.12.1"},
    {"name": "node", "path": "/usr/bin/node", "version": "20.11.0"}
  ],
  "agent_mode": true,
  "max_concurrent_executions": 10,
  "worker_version": "0.1.0"
}

Standard attune-worker registrations are unchanged — no detected_interpreters or agent_mode keys.

Phase 2 Sub-tasks

Sub-task	Status	Notes
2.1 Interpreter Discovery Module	✅ Done (Phase 1)	runtime_detect.rs already existed
2.2 Integration with Worker Registration	✅ Done	Rich capabilities + agent_mode flag
2.3 Runtime Hints File	⏭️ Deferred	Optional enhancement, not needed yet

Verification

• cargo check --workspace — zero errors, zero warnings
• cargo test -p attune-worker — all tests pass (unit, integration, doc-tests)
• No breaking changes to the standard attune-worker binary