expansion-grant-guard（扩展授予守卫）

Expansion Grant Guard

What it does

When an agent delegates work to a sub-agent (or expands context via DAG recall), it needs a controlled way to grant scoped permissions. Expansion Grant Guard maintains a YAML-based grant ledger that issues time-limited, token-budgeted grants — ensuring sub-agent operations stay within defined boundaries.

Inspired by lossless-claw's delegation grant system, where a parent agent issues a signed grant specifying what a sub-agent can access, how many tokens it may consume, and when the grant expires.

When to invoke

• Before any sub-agent expansion or delegation — issue a grant first
• When a sub-agent requests resources — validate the grant before proceeding
• When checking token budgets — verify remaining budget in the grant
• Periodically to clean up expired grants — auto-expiry sweep

How to use

python3 guard.py --issue --scope "dag-recall" --budget 4000 --ttl 30   # Issue a grant
python3 guard.py --validate <grant-id>                                  # Check if grant is valid
python3 guard.py --consume <grant-id> --tokens 500                     # Record token usage
python3 guard.py --revoke <grant-id>                                    # Revoke a grant early
python3 guard.py --list                                                 # List all active grants
python3 guard.py --sweep                                                # Clean up expired grants
python3 guard.py --audit                                                # Full audit log
python3 guard.py --stats                                                # Grant statistics
python3 guard.py --status                                               # Current status summary
python3 guard.py --format json                                          # Machine-readable output

Grant structure

Each grant is a YAML entry in the ledger:

grant_id: "g-20260316-001"
scope: "dag-recall"           # What the grant allows
issued_at: "2026-03-16T10:00:00Z"
expires_at: "2026-03-16T10:30:00Z"
token_budget: 4000            # Max tokens allowed
tokens_consumed: 1250         # Tokens used so far
status: active                # active | expired | revoked | exhausted
issuer: "parent-session"
metadata:
  query: "auth migration"
  reason: "Recalling auth decisions for new implementation"

Grant lifecycle

Issue → Active → { Consumed | Expired | Revoked | Exhausted }
  │                    │
  │                    ├─ tokens_consumed < budget → still active
  │                    ├─ tokens_consumed >= budget → exhausted
  │                    ├─ now > expires_at → expired
  │                    └─ explicit revoke → revoked
  │
  └─ Validation checks: status=active AND not expired AND budget remaining

Procedure

Step 1 — Issue a grant before expansion

python3 guard.py --issue --scope "dag-recall" --budget 4000 --ttl 30

Output:

Grant Issued
─────────────────────────────────────────────
  Grant ID:     g-20260316-001
  Scope:        dag-recall
  Token budget: 4,000
  Expires:      2026-03-16T10:30:00Z (in 30 min)
  Status:       active

Step 2 — Validate before consuming resources

python3 guard.py --validate g-20260316-001

Returns status, remaining budget, and time until expiry. Non-zero exit code if invalid.

Step 3 — Record token consumption

python3 guard.py --consume g-20260316-001 --tokens 1250

Deducts from the grant's remaining budget. Fails if exceeding budget.

Step 4 — Sweep expired grants

python3 guard.py --sweep

Marks all expired grants and cleans up the active list.

Scope types

• dag-recall — Permission to walk DAG nodes and assemble answers
• session-search — Permission to search session persistence database
• file-access — Permission to read externalized large files
• context-expand — Permission to expand context window with external data
• tool-invoke — Permission to invoke external tools/MCP servers
• Custom scopes accepted — any string is valid

Integration with other skills

• dag-recall: Should issue a grant before expanding DAG nodes; checks budget during expansion
• session-persistence: Grant-gated search — validate grant before querying message database
• large-file-interceptor: Grant-gated file restore — validate before loading large files back
• context-assembly-scorer: Token budget tracking feeds into assembly scoring

State

Grant ledger and audit log stored in ~/.openclaw/skill-state/expansion-grant-guard/state.yaml.

Fields: active_grants, total_issued, total_expired, total_revoked, total_exhausted, total_tokens_granted, total_tokens_consumed, grant_history.

Notes

• Uses Python's built-in modules only — no external dependencies
• Grant IDs are timestamped and sequential within a day
• Ledger file is append-friendly YAML — safe for concurrent reads
• Expired grants kept in history for audit; active list stays clean after sweep
• Default TTL is 30 minutes; max TTL is 24 hours
• Token budget is advisory — enforcement depends on consuming skill cooperation