Remove shared trajectory index file

IMPLEMENTATION-PROPOSAL.md

@@ -619,12 +619,13 @@ agent-trajectories/
 
 ```
 .trajectories/
-├── index.json                # Quick lookup index
 ├── active/
-│   └── traj_abc123.json
+│   └── traj_abc123/
+│       └── trajectory.json
 ├── completed/
 │   └── 2024-01/
-│       └── traj_def456.json
+│       └── traj_def456/
+│           └── trajectory.json
 └── archive/
 ```
 
@@ -633,11 +634,12 @@ agent-trajectories/
 - Git-friendly (version with code)
 - Human-readable/editable
 - Works everywhere
+- No shared mutable index file to merge
 
 **Cons:**
 - No efficient querying
 - No full-text search
-- Index can get out of sync
+- Directory scans may become expensive at very large scales
 - Large repos = slow listing
 
 **Best for:** Simple setups, single-agent use, git-centric workflows

README.md

@@ -132,14 +132,14 @@ trail compact --commits abc1234,def5678  # Trajectories matching specific commit
 trail compact --pr 123                # Trajectories mentioning PR #123
 trail compact --since 7d              # Last 7 days
 trail compact --all                   # Everything (including previously compacted)
-trail compact --pr 123 --discard-sources  # Delete source trajectories and update index after compaction
+trail compact --pr 123 --discard-sources  # Delete source trajectories after compaction
 ```
 
 ### Automatic Compaction (GitHub Action)
 
 Add these steps to any workflow that runs on PR merge (e.g., your release or publish flow). Requires `ref: ${{ github.event.pull_request.base.ref }}` and `fetch-depth: 0` on checkout, plus `contents: write` permission.
 
-Use `--discard-sources` when the compacted summary should replace the raw source trajectories. This removes the source JSON/Markdown/trace files and updates `.trajectories/index.json`, reducing future list/search noise.
+Use `--discard-sources` when the compacted summary should replace the raw source trajectories. This removes the source JSON/Markdown/trace files, reducing future list/search noise.
 
 ```yaml
       - name: Compact trajectories

docs/architecture/core.md

@@ -309,29 +309,17 @@ Recommend users add to `.gitignore`:
 
 ## Performance Considerations
 
-### Index for Fast Lookups
-
-Maintain `index.json` for quick listing without reading all files:
-
-```json
-{
-  "version": 1,
-  "lastUpdated": "2024-01-15T10:00:00Z",
-  "trajectories": {
-    "traj_abc123": {
-      "title": "Implement auth",
-      "status": "completed",
-      "startedAt": "2024-01-15T08:00:00Z",
-      "completedAt": "2024-01-15T10:00:00Z"
-    }
-  }
-}
-```
+### Directory Scans for Lookups
+
+List and search commands scan per-trajectory files under `active/` and
+`completed/`. Keeping each trajectory in its own directory avoids a shared
+mutable index file and reduces merge conflicts when multiple branches add
+trajectories.
 
 ### Lazy Loading
 
 Only load full trajectory data when needed:
-- `list` command reads only index
+- `list` command scans trajectory files and reads summary metadata
 - `show` command loads full trajectory
 - `search` may need to load all (acceptable for v1, optimize later with SQLite)
 
@@ -347,13 +335,14 @@ Warn users if trajectory exceeds reasonable size:
 
 ```
 .trajectories/
-├── index.json              # Quick lookup index
 ├── active/                 # In-progress trajectories
-│   └── traj_abc123.json
+│   └── traj_abc123/
+│       └── trajectory.json
 ├── completed/              # Finished trajectories
 │   └── 2024-01/            # Organized by month
-│       ├── traj_def456.json
-│       └── traj_def456.md  # Auto-generated markdown
+│       └── traj_def456/
+│           ├── trajectory.json
+│           └── summary.md  # Auto-generated markdown
 └── .gitignore              # Ignore active/, keep completed/
 ```
 

docs/trail-snippet.md

@@ -83,17 +83,16 @@ trail complete --summary "Added JWT auth with refresh tokens" --confidence 0.85
 
 After completing work, compact the finished trajectory or merged PR into a
 durable summary. When the compacted summary is sufficient, discard the raw
-source trajectories so `.trajectories/index.json` and list output stay focused:
+source trajectories so list output stays focused:
 
 ```bash
 trail compact --discard-sources
 # or after a PR merge:
 trail compact --pr 42 --discard-sources
 ```
 
-`--discard-sources` removes the source trajectory JSON/Markdown/trace files and
-updates the index. Use it after confirming the compacted artifact is the record
-you want to keep.
+`--discard-sources` removes the source trajectory JSON/Markdown/trace files. Use
+it after confirming the compacted artifact is the record you want to keep.
 
 **Confidence levels:**
 - 0.9+ : High confidence, well-tested
@@ -154,7 +153,7 @@ trail compact --commits abc123,def456 --discard-sources
 
 Compaction consolidates decisions and creates a grouped summary. Adding
 `--discard-sources` makes the compacted artifact the durable record by removing
-the raw trajectories and their index entries.
+the raw trajectories.
 
 ## Why Trail?
 

package.json

@@ -48,9 +48,7 @@
     "type": "git",
     "url": "https://github.com/AgentWorkforce/trajectories"
   },
-  "files": [
-    "dist"
-  ],
+  "files": ["dist"],
   "engines": {
     "node": ">=20.0.0"
   },