16d45d9a11
Alignment dialogues now use custom `alignment-expert` subagents with max_turns: 10, tool restrictions (Read/Grep/Glob), and hard 400-word output limits. Judge protocol injects as prose via RFC 0023. Moved Blue voice patterns from CLAUDE.md to MCP server instructions field for cross-repo portability. Includes RFCs 0017-0026, spikes, and alignment dialogues from 2026-01-25/26 sessions. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
94 lines
3 KiB
Markdown
94 lines
3 KiB
Markdown
# Spike: MCP Project Detection
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| **Status** | In Progress |
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| **Date** | 2026-01-26 |
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| **Time Box** | 30 minutes |
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---
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## Question
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Why does the Blue MCP server fail to detect the project directory, and what's the correct solution?
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---
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## Investigation
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### Current Behavior
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1. Claude Code starts Blue MCP server via `blue mcp`
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2. Server starts with unknown working directory
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3. First tool call without `cwd` param fails: "Blue not detected in this directory"
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4. Tool call with explicit `cwd` works
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### Root Cause Analysis
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**Hypothesis 1: Process working directory**
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- MCP servers are child processes of Claude Code
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- Working directory may be Claude Code's install location, not project
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**Hypothesis 2: MCP protocol provides workspace info**
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- MCP spec has `roots` capability for filesystem boundaries
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- Claude Code may send roots during initialize or via `roots/list`
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**Hypothesis 3: Environment variables**
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- Claude Code sets `CLAUDECODE=1`, `CLAUDE_CODE_SSE_PORT`, `CLAUDE_CODE_ENTRYPOINT`
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- No project path variable observed
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### MCP Protocol Research
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Per [MCP Specification](https://modelcontextprotocol.io/specification/2025-11-25):
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1. **Roots** - Servers can request roots from clients
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2. **Initialize params** - May contain client capabilities but not workspace path
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3. **No standard workspace field** - Unlike LSP's `rootUri`/`workspaceFolders`
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### Attempted Fixes
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| Attempt | Result |
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|---------|--------|
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| Fall back to `current_dir()` | Failed - wrong directory |
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| Parse `roots` from initialize | Unknown - needs testing |
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| Walk up directory tree | Implemented but untested |
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### Key Finding
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**The MCP protocol does not provide a standard way for servers to know the user's project directory.** This is a gap compared to LSP.
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### Options Discovered
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1. **Require `cwd` in every tool call** - Current workaround, verbose
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2. **Walk up directory tree** - Find `.blue/` from process cwd
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3. **Use MCP roots** - Request roots from client, use first root
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4. **Wrapper script** - Shell wrapper that sets cwd before starting server
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5. **Config file** - Store project path in `~/.blue/projects.json`
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---
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## Alignment Dialogue Result
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6 experts, 98% convergence on **Option 1: C → B → fail**
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| Round | Result |
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|-------|--------|
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| R1 | B (3), C (2), Combined (1) |
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| R2 | Option 1 (3), Option 2 (2), Option 3 (1) |
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| R3 | Option 1 unanimous |
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**Consensus**: MCP roots first → Walk tree fallback → Fail with guidance
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The current code already implements this. The remaining issue is that:
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1. Claude Code may not send roots during initialize
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2. Process cwd starts outside project tree (e.g., $HOME)
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---
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## Conclusion
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**Root cause**: Claude Code starts MCP servers from a non-project directory and doesn't send MCP roots.
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**Solution**: The C → B fallback chain is correct. Need to verify Claude Code sends roots, or ensure walk-tree can find project from wherever the process starts.
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**Recommended next step**: Draft RFC to formalize the detection algorithm and add better error messaging.
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