Provider Sessions

This page keeps the historical agent-runner-ipc.md path for old links, but the current implementation no longer has an in-tree agent-runner crate or IPC server. Provider execution now routes through orchestrator-plugin-host::session and installed provider plugins.

Source Files

Area	Source
Agent runtime entrypoint	crates/orchestrator-cli/src/services/runtime/runtime_agent/run.rs
Provider client	crates/orchestrator-cli/src/services/runtime/runtime_agent/provider_client.rs
Session resolver	crates/orchestrator-plugin-host/src/session/session_backend_resolver.rs
Plugin backend	crates/orchestrator-plugin-host/src/session/plugin_backend.rs
Plugin supervisor	crates/orchestrator-plugin-host/src/session/plugin_supervisor.rs
Runtime contract wiring	crates/orchestrator-core/src/runtime_contract.rs

Current Flow

The resolver discovers plugins with plugin_kind == "provider". There is no in-tree provider fallback and no separate Unix-socket sidecar.

Session Model

Important behavior in the current path:

• animus agent run starts a provider-owned session through the plugin host.
• animus agent status and animus agent control operate on the live provider session tracked by the resolver.
• agent/resume resumes a provider-owned session when that plugin supports it.
• Provider plugin cwd is pinned to the resolved project_root so relative state and child CLI paths stay anchored to the repository.
• Structured JSON-RPC errors from the provider plugin surface directly to the caller.
• Restart handling lives in the plugin supervisor rather than a standalone runner daemon.

Environment And Tool Resolution

Provider selection and launch behavior are driven by the runtime contract and tool routing code:

• default models live in protocol::default_model_for_tool
• CLI capability mapping lives in crates/orchestrator-core/src/runtime_contract.rs
• the OpenAI-compatible runner now resolves to the installed launchapp-dev/animus-provider-oai-agent plugin rather than an in-tree binary

Reserved first-party provider names currently include claude, codex, gemini, opencode, and oai.

Historical Note

Older versions used a separate agent-runner sidecar and IPC transport. That design was removed in the v0.5.3 surface-shrink. If you are tracing legacy behavior, prefer historical architecture notes or tagged source snapshots over this page.