SouveraineOS/docs/substrate/issues/002-concurrent-turn-context-race.md

id	title	status	priority	created	area
002	Concurrent turns race on the global Sensorium	open	medium	2026-05-08	tool-substrate

Problem

If two turns execute concurrently (e.g. HTTP server handling two agent conversations, or a subconscious N+1 pass running alongside a primary turn), both would share the global Sensorium including its ToolContext. This means:

1. Turn A sets ToolContext to agent A's memory root
2. Turn B sets ToolContext to agent B's memory root
3. Turn A's tool executes — checks agent B's boundary → false positive or false negative

Current architecture constraints

• Sensorium is a OnceLock at src/core/tools/mod.rs:164 — globally shared
• The bash BashState (cwd, env, background tasks) lives inside the shared Sensorium as Arc<Mutex<BashState>>
• Two agents running simultaneously would also share bash state — cwd from one leaks into the other

Consideration: is this actually a problem today?

Currently:

• LocalBackend::send() spawns a single run_turn() per conversation — sequential per conversation
• The HTTP server may handle multiple conversations but each streams via its own SSE channel
• N+1 subconscious is synchronous (no LLM call, just heuristic) — can't race with primary

If/when N+1 becomes an async LLM call with tool access, or when the HTTP server dispatches concurrent turns, this race becomes real.

Possible approaches

• Pass agent context through execute_tool() parameter (resolves the ToolContext race)
• But bash state is still shared — would need per-agent BashState or explicit isolation
• Or defer bash state isolation until concurrent turns are actually wired

References

• src/backend/local.rs:98-328 — single-threaded run_turn()
• src/core/tools/mod.rs:62-75 — Sensorium::new() creates shared Bash
• src/core/tools/bash.rs — BashState in Arc<Mutex<>>

Status

This is not actionable today — no concurrent turns exist. It becomes actionable when: a) HTTP server dispatches concurrent turns, OR b) Async N+1 runs alongside primary turn with tool access