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

Universal Worker Agent Phase 2: Runtime Detection ↔ Worker Registration Integration

Date: 2026-02-05

Summary

Integrated the Phase 1 runtime auto-detection module with the worker registration system so that attune-agent workers register with rich interpreter metadata (binary paths, versions) in their capabilities, enabling the system to distinguish agents from standard workers and know exactly which interpreters are available and where.

Changes

1. crates/worker/src/runtime_detect.rs

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

2. crates/worker/src/registration.rs

• Added use crate::runtime_detect::DetectedRuntime import.
• Added set_detected_runtimes(&mut self, runtimes: Vec<DetectedRuntime>) method that stores detected interpreter metadata under the detected_interpreters capability key as a JSON array of {name, path, version} objects.
• Added set_agent_mode(&mut self, is_agent: bool) method that sets an agent_mode boolean capability to distinguish agent workers from standard workers.
• Both methods are additive — the existing runtimes string list capability remains for backward compatibility.

3. crates/worker/src/service.rs

• Added detected_runtimes: Option<Vec<DetectedRuntime>> field to WorkerService (initialized to None in new()).
• Added pub fn with_detected_runtimes(mut self, runtimes: Vec<DetectedRuntime>) -> Self builder method that stores agent detection results for use during start().
• Updated start() to call registration.set_detected_runtimes() and registration.set_agent_mode(true) before register() when detected runtimes are present.
• Standard attune-worker binary is completely unaffected — the field stays None and no agent-specific code runs.

4. crates/worker/src/agent_main.rs

• Added agent_detected_runtimes: Option<Vec<DetectedRuntime>> variable to stash detection results.
• After auto-detection runs and sets ATTUNE_WORKER_RUNTIMES, the detected Vec is saved into agent_detected_runtimes.
• After WorkerService::new(), calls .with_detected_runtimes(detected) if auto-detection ran, so the registration includes full interpreter metadata.

5. crates/worker/src/lib.rs

• Added pub use runtime_detect::DetectedRuntime re-export for convenient access.

Capability Format

After Phase 2, an agent worker's capabilities JSON in the worker table looks like:

{
  "runtimes": ["shell", "python", "node"],
  "max_concurrent_executions": 10,
  "worker_version": "0.1.0",
  "agent_mode": true,
  "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"}
  ]
}

Standard attune-worker instances do NOT have agent_mode or detected_interpreters keys.

Design Decisions

• Builder pattern (with_detected_runtimes) rather than a separate constructor — keeps the API surface minimal and avoids duplicating new() logic.
• Explicit set_agent_mode separate from set_detected_runtimes — allows independent control, though in practice they're always called together for agents.
• JSON serialization via serde_json::json!() macro rather than serde_json::to_value(&runtimes) — gives explicit control over the capability shape and avoids coupling the DB format to the Rust struct layout.
• No changes to the Worker model or database schema — detected_interpreters and agent_mode are stored inside the existing capabilities JSONB column.

Verification

• cargo check --workspace — zero errors, zero warnings
• cargo test -p attune-worker — 139 tests pass (105 unit + 17 dependency isolation + 8 log truncation + 7 security + 2 doc-tests)
• Standard attune-worker binary path is completely unchanged