Cache Clear

Your responsibility is to remove entries from the codex cache by delegating to the cli-helper skill which invokes the fractary codex cache clear CLI command.

Architecture (v4.0):

cache-clear skill
  ↓ (delegates to)
cli-helper skill
  ↓ (invokes)
fractary codex cache clear
  ↓ (uses)
@fractary/codex SDK (CacheManager)

This provides safe cache deletion with confirmation, dry-run previews, and atomic index updates via the TypeScript SDK.

Step 1: Validate Scope

Check that scope is one of: all, expired, pattern

IF scope is invalid:

• Error: "Invalid scope"
• List valid scopes: all, expired, pattern
• STOP

IF scope == "all" AND confirmed != true:

• Set dry_run = true (force preview first)
• Continue to show what would be deleted
• Then ask for confirmation

Step 2: Build CLI Arguments

Construct arguments array from inputs:

args = ["cache", "clear"]

// Add scope
if (scope === "all") args.push("--all")
if (scope === "expired") args.push("--expired")
if (scope === "pattern" && filter?.pattern) {
  args.push("--pattern", filter.pattern)
}

// Add dry-run flag if requested or scope=all without confirmation
if (dry_run || (scope === "all" && !confirmed)) {
  args.push("--dry-run")
}

Step 3: Delegate to CLI Helper

USE SKILL: cli-helper Operation: invoke-cli Parameters:

{
  "command": "cache",
  "args": ["clear", ...scope_flags, ...dry_run_flag],
  "parse_output": true
}

The cli-helper will:

1. Validate CLI installation
2. Execute: fractary codex cache clear [--all|--expired|--pattern <p>] [--dry-run] --json
3. Parse JSON output
4. Return results

Step 4: Process CLI Response

The CLI returns JSON like:

Dry-Run:

{
  "status": "success",
  "operation": "cache-clear",
  "dry_run": true,
  "would_delete": {
    "count": 4,
    "size_bytes": 8483,
    "entries": [
      {
        "uri": "codex://fractary/old-service/README.md",
        "size_bytes": 5242,
        "reason": "Expired 5 days ago"
      }
    ]
  }
}

Actual Deletion:

{
  "status": "success",
  "operation": "cache-clear",
  "dry_run": false,
  "deleted": {
    "count": 4,
    "size_bytes": 8483,
    "entries": [...]
  },
  "cache_stats": {
    "before": {"total_entries": 42, "total_size_bytes": 3355443},
    "after": {"total_entries": 38, "total_size_bytes": 3347960}
  }
}

IF status == "success" AND dry_run == true:

• Display preview (see OUTPUTS section)
• IF scope == "all": Ask for confirmation
• STOP (wait for user action)

IF status == "success" AND dry_run == false:

• Display deletion results (see OUTPUTS section)
• DONE ✅

IF status == "failure":

• Extract error message from CLI
• Return error to caller
• DONE (with error)

Step 5: Handle Confirmation (scope=all only)

IF scope == "all" AND dry_run preview shown:

• Ask user: "Delete entire cache? This will remove {count} entries ({size})"
• Options:
  • "Yes, delete all" → Retry with confirmed=true, dry_run=false
  • "Cancel" → STOP
• STOP (wait for user choice)

Step 6: Return Results

Display formatted output to user.

COMPLETION: Operation complete when results shown.

✅ For dry-run:

• CLI invoked successfully
• Preview displayed to user
• User informed of next steps

✅ For actual deletion:

• CLI invoked successfully
• Entries deleted
• Cache index updated atomically
• Results displayed to user

✅ For failed clear:

• Error captured from CLI
• Error message clear and actionable
• Results returned to caller

✅ In all cases:

• No direct script execution
• CLI handles all operations
• Structured response provided

Dry-Run Output

🔍 DRY-RUN: Cache Clear Preview
───────────────────────────────────────
Would delete 4 entries (8.3 KB):

⚠ codex://fractary/old-service/README.md (5.1 KB)
  Reason: Expired 5 days ago

⚠ codex://fractary/deprecated/guide.md (3.2 KB)
  Reason: Expired 7 days ago

Total to delete: 8.3 KB
───────────────────────────────────────
Run without --dry-run to execute

Actual Deletion Output

🗑️  CACHE CLEAR COMPLETED
───────────────────────────────────────
Deleted 4 entries (8.3 KB):

✓ codex://fractary/old-service/README.md
✓ codex://fractary/deprecated/guide.md
✓ codex://fractary/temp-service/notes.md
✓ codex://fractary/archived/spec.md

Cache stats updated:
- Total entries: 38 (was 42)
- Total size: 3.1 MB (was 3.2 MB)
───────────────────────────────────────
Cache index updated automatically

Documents will be re-fetched when accessed.

Confirmation Required (scope=all)

⚠️  CONFIRMATION REQUIRED: Delete entire cache

This will delete ALL cached documents:
- Total entries: 42
- Total size: 3.2 MB

Cache is regeneratable - source documents are not affected.
Deleted documents will be re-fetched automatically when accessed.

Delete entire cache?
[Yes, delete all] [Cancel]

No Matches

ℹ️  CACHE CLEAR: No entries found

No entries matched the specified filter.

Filter: {filter description}
Current cache size: {count} entries ({size})
───────────────────────────────────────
Use /fractary-codex:cache-list to view cache

Failure Response: CLI Error

{
  "status": "failure",
  "operation": "cache-clear",
  "error": "Failed to delete cache entries",
  "cli_error": {
    "message": "Permission denied writing to cache index",
    "suggested_fixes": [
      "Check file permissions",
      "Ensure cache directory is writable"
    ]
  }
}

Failure Response: CLI Not Available

{
  "status": "failure",
  "operation": "cache-clear",
  "error": "CLI not available",
  "suggested_fixes": [
    "Install globally: npm install -g @fractary/cli",
    "Or ensure npx is available"
  ]
}

Index Missing

When CLI reports cache index doesn't exist:

1. Show "Cache is already empty" message
2. NOT an error condition
3. Explain this is normal for new installations

Script Failure

When CLI returns error:

1. Preserve exact error message from CLI
2. Include suggested fixes if CLI provides them
3. Add context about what was being cleared
4. Return structured error

Filesystem Error

When CLI reports file deletion failures:

1. Show CLI's error message
2. Explain which files failed
3. Note that CLI uses best-effort deletion
4. Index reflects actual state

No Scope

When scope is missing or invalid:

1. Return error with valid scope list
2. Provide examples for each scope
3. Suggest using --dry-run to preview

CLI Not Available

When cli-helper reports CLI unavailable:

1. Pass through installation instructions
2. Don't attempt workarounds
3. Return clear error to caller

Success (Dry-Run):

🎯 STARTING: cache-clear
Scope: {scope}
Filter: {filter details}
Mode: DRY-RUN
───────────────────────────────────────

[Preview of entries to delete]

✅ COMPLETED: cache-clear (dry-run)
Would delete {count} entries ({size})
Source: CLI (via cli-helper)
───────────────────────────────────────

Success (Actual Deletion):

🎯 STARTING: cache-clear
Scope: {scope}
Filter: {filter details}
Mode: EXECUTE
───────────────────────────────────────

[Deletion results]

✅ COMPLETED: cache-clear
Deleted {count} entries ({size})
Cache index updated
Source: CLI (via cli-helper)
───────────────────────────────────────
Documents will be re-fetched when accessed

Failure:

🎯 STARTING: cache-clear
───────────────────────────────────────

❌ FAILED: cache-clear
Error: {error_message}
Suggested fixes:
- {fix 1}
- {fix 2}
───────────────────────────────────────

Migration from v3.0

v3.0 (bash scripts):

cache-clear
  └─ scripts/clear-cache.sh
      ├─ reads cache index
      ├─ deletes files
      ├─ updates index atomically
      └─ handles errors

v4.0 (CLI delegation):

cache-clear
  └─ delegates to cli-helper
      └─ invokes: fractary codex cache clear

Benefits:

• ~95% code reduction in this skill
• TypeScript type safety from SDK
• Atomic index updates guaranteed by SDK
• Better error messages
• Built-in dry-run support
• Automatic confirmation handling

CLI Command Used

This skill delegates to:

fractary codex cache clear [--all|--expired|--pattern <pattern>] [--dry-run] --json

SDK Features Leveraged

Via the CLI, this skill benefits from:

• CacheManager.clear() - Main deletion logic
• Atomic index updates (write to temp, then rename)
• Best-effort file deletion
• Automatic stats calculation
• Built-in dry-run support

Safety Features

1. Confirmation for --all: CLI enforces confirmation prompt
2. Dry-run by default for scope=all: Shows impact before deletion
3. Atomic index updates: SDK guarantees consistency
4. Best-effort deletion: Continues even if some files fail
5. Index reflects reality: Always updated to match filesystem

Scope Examples

Clear expired (safe, no confirmation):

{
  "scope": "expired"
}

Clear by pattern:

{
  "scope": "pattern",
  "filter": {"pattern": "**/*.md"}
}

Clear all (requires confirmation):

{
  "scope": "all",
  "confirmed": true
}

Dry-run first:

{
  "scope": "all",
  "dry_run": true
}

Cache Regeneration

All deleted entries will be automatically re-fetched when accessed:

• Next /fractary-codex:fetch retrieves from source
• Cache repopulated with fresh content
• TTL reset to configured default

Testing

To test this skill:

# Ensure CLI installed
npm install -g @fractary/cli

# Populate cache first
fractary codex fetch codex://fractary/codex/README.md

# Test dry-run
USE SKILL: cache-clear
Parameters: {
  "scope": "expired",
  "dry_run": true
}

# Test actual deletion
USE SKILL: cache-clear
Parameters: {
  "scope": "expired"
}

Troubleshooting

If clear fails:

1. Check CLI installation: fractary --version
2. Check permissions: Cache directory must be writable
3. Test CLI directly: fractary codex cache clear --expired
4. Check cache index: fractary codex cache list
5. Run health check: fractary codex health