bug(cursor): system prompt says “openpi MCP tools” while advertised names are read/rg/bash [under investigation]

[tt-a1i]

Status

Under investigation. Isolated reliability work against v0.8.1 (a3edee28). Not a formal Benchmark.

Impact

CURSOR_PI_TOOLS_SYSTEM_PROMPT (extensions/ai-providers/cursor/tool-bridge.ts) tells the model to use “the provided openpi MCP tools” and not Cursor-native tools. Advertised Pi tool names remain read / rg / bash. On some cursor-grok-4.6-high-fast class-A runs the model completed 23–24 successful read+rg calls, then looped claiming it had used Cursor-native / non-mcp_openpi_* wrappers and never wrote the acceptor file (harness timeout). Distinct from connection timeout, cancel, and native-exec rejection.

Evidence

• Class A, cursor-grok-4.6-high-fast, attempts 01 and 04 of 5: timeout after many successful Pi tools; no ACCEPT_A.
• Same cell on cursor-grok-4.6-high: 5/5 correct.
• Class C on high-fast: 5/5 with a recorded native_rejection then Pi recovery (PR fix(cursor): recover from native tool requests without native execution #484 path works when a native request actually occurs).
• Prompt is not snapshotted in tests today.

Unblock

Need a prompt-wording repro that does not collapse into “the model was slow,” then a minimal prompt change that names the advertised tool IDs, plus ≥10 before/after on the same A task+acceptor. Do not disable tools or swallow the loop.

Applicability

OpenPI Cursor provider, v0.8.1. Related: #234 / PR #484 (native exec rejection) — this issue is leftover identity/loop behavior after tools already succeeded.