claude-code - 💡(How to fix) Fix [Bug] Warp terminal AI layer causes agent cognitive degradation and parallel agent isolation failures [1 comments, 2 participants]

Problem

When running Claude Code inside Warp terminal (free tier), two distinct failures occur that do NOT reproduce in plain terminals (Alacritty, kitty, native Terminal):

1. Parallel agents violate file boundaries — subagents edit files owned by other parallel agents and race to commit, ignoring worktree/directory isolation
2. Severe cognitive degradation ("降智") — the model performs nonsensical actions such as creating frontend source code inside docs/architecture_decisions/, then rationalizing it by claiming it intends to migrate README files into web/. The same model + same CLAUDE.md on a clean terminal does not exhibit this.

Root cause hypothesis

Warp's architecture introduces multiple I/O interception layers on the same PTY stream that Claude Code reads:

• Shell integration hooks: DCS escape sequences injected into PTY for command block segmentation (\eP$f{"hook": "SourcedRcFileForWarp", ...}\x9c)
• Proactive AI: On the free tier, this cannot be disabled. It parses all stdout in real-time, potentially injecting AI suggestion metadata back into the stream
• Command block parser: Real-time ANSI parsing that segments output — may interleave or truncate tool results from concurrent subagent subprocesses

The net effect: Claude Code's tool results and system prompt context get polluted with Warp-injected metadata, causing:

• Premature autocompact (CLAUDE.md rules lost → model forgets project structure)
• Cross-contamination between parallel agent stdout streams
• Model receiving truncated or corrupted tool results, forced to hallucinate

Evidence

Incident 1: Frontend code in docs/ directory

• Branch: adr/0206_ia_atomization (architecture documentation branch)
• Model: Claude Opus 4.7 1M (OAuth, user's own API key)
• Terminal: Warp (free tier, macOS/WSL2)
• Behavior: Agent created Svelte component files inside docs/01_architecture_decisions/
• When questioned, rationalized: "planning to migrate README.toml and markdown into web/"
• Same session context in Alacritty: does not reproduce

Incident 2: Parallel agent commit racing

• Multiple subagents launched via Agent tool with isolation: "worktree"
• Agents edited files in each other's worktrees
• Agents raced to git commit, causing lock conflicts and incorrect staged files
• Consistent with #47266, #45815, #48927 but Warp worsens the failure mode

Related issues

• #48028 — Context loss at <40% utilization (same symptom, possibly same root cause)
• #43038 — Warp + worktree causes pane split and agent stall
• #45815 — Sessions ignore worktree isolation rules
• #47266 — Parallel worktree agents hit git lock race condition
• #10375 — Terminal escape sequences leak into Claude Code input
• #34332 — Autocompact fires prematurely on 1M Opus

Warp-side issues:

• warpdotdev/Warp#8409, #8805 — 100% CPU hang during Claude Code sessions
• warpdotdev/Warp#9365 — Rendering corruption with Claude Code's alt-screen

Steps to reproduce

1. Open Warp terminal (free tier, Proactive AI enabled — cannot be disabled)
2. Run claude with a large CLAUDE.md (10K+ tokens of project rules)
3. Launch 2+ parallel subagents via Agent tool
4. Observe: agents cross file boundaries, commit races, and/or nonsensical actions
5. Repeat in Alacritty/kitty with identical CLAUDE.md — issue does not reproduce

Expected behavior

• Claude Code should be resilient to terminal-layer I/O interception
• Parallel agent isolation should hold regardless of terminal emulator
• Tool results should not be corrupted by terminal escape sequences or AI overlays

Suggested mitigations

1. Detect Warp ($WARP_IS_LOCAL_SHELL_SESSION == 1) and warn users about known compatibility issues
2. Sanitize tool results — strip non-standard DCS/escape sequences before feeding into model context
3. Document terminal compatibility — recommend plain terminals for agent-heavy workflows in official docs

Environment

• Claude Code CLI (latest)
• Warp terminal (free tier)
• Platform: Linux (WSL2) / macOS
• Model: Claude Opus 4.7 1M (OAuth)
• CLAUDE.md size: ~15K tokens (heavy rule set)