Agent: loop prompts reference non-existent .ralph/AGENTS.md

[federiconeri]

Summary

Loop prompt templates reference @.ralph/AGENTS.md which doesn't exist, causing failed file reads in every session that uses those prompts.

Problem / Context

During the second agent test, sessions 1 and 3 both errored trying to read .ralph/AGENTS.md:

• Session 1 (planning): 5 AGENTS.md references, file-not-found errors
• Session 3 (pr-review): 6 AGENTS.md references, file-not-found errors

Each failed read wastes an API turn (~53K tokens of context re-read) and adds noise to the session.

Root Cause

Two prompt templates contain Study @.ralph/AGENTS.md for commands and patterns:

• .ralph/prompts/PROMPT_feature.md (line 2)
• .ralph/prompts/PROMPT_review_manual.md (line 2)

The file .ralph/guides/AGENTS.md exists but at a different path than what the prompts reference.

Proposed Solution

Either:

1. Fix the path: Change @.ralph/AGENTS.md → @.ralph/guides/AGENTS.md in the prompt templates
2. Remove the reference: If the guides content isn't useful for loop sessions, remove the line entirely

This is a ralph-side fix (prompt templates), but wiggum's agent mode should validate that referenced files exist before spawning sessions.

Files to Modify

File	Changes
src/agent/tools/execution.ts	Consider validating prompt template file references before spawning

Acceptance Criteria

• No "file not found" errors for AGENTS.md in loop sessions
• Agent validates or warns about missing referenced files in prompts