`src/config.rs` — `SessionConfig`

Session-scoped settings, stable across runs on one agent.

Key items

• SessionConfig { system_prompt: Option<String>, context_window: u64, compact_threshold: u8, auto_compact: bool }
• Defaults: None, 200,000, 80, true.
• Builders: with_system_prompt, with_context_window, with_compact_threshold (clamped 0–100), with_auto_compact.
• ParallelMode { Sequential, Parallel } and ParallelDispatchConfig { mode, max_concurrency } — defaults Sequential / 8; clamped to [1, batch size] at dispatch.

Behavior notes

• Threshold comparison in the machine is strict (>); the emergency line at 95% is inclusive (>=) and always on.
• compact_threshold: 0 disables the threshold trigger; context_window: 0 disables all window policy.
• Serde deserialization clamps out-of-range thresholds to 100 (won’t round-trip the original number); direct struct construction bypasses clamping entirely — prefer builders.
• max_turns is not here — it’s per-run, on RunConfig.

Deep dive: Session config.