anti-drift

name	anti-drift
description	Prevents agent divergence from task intent through checkpoint validation, scope monitoring, and alignment gates. Detects scope creep, time overruns, and error cascades, then forces re-alignment before work continues. Use when: multi-agent tasks, complex implementations, long-running sessions. Skip when: trivial single-step tasks, pure research.
tags	["orchestration","quality","agents"]
triggers	["anti drift","use anti drift","run anti drift"]
tier	standard

Anti-Drift — Agent Alignment & Divergence Prevention

Purpose: Agents solving complex tasks will drift from the original intent. This skill detects drift early and forces re-alignment before wasted work compounds.

Why This Matters

Without anti-drift:

• Agent starts fixing a bug, ends up refactoring 12 files nobody asked for
• Multi-agent task has each agent making conflicting assumptions
• 30-minute task balloons to 2 hours because scope expanded silently
• Agent retries the same failing approach 5 times instead of escalating

With anti-drift:

• Checkpoint every N steps forces "am I still on track?"
• Scope monitor flags when files touched exceed the plan
• Error cascade detector stops thrashing after 2 consecutive failures
• Time overrun detector flags when work exceeds 2x the estimate

The Three Drift Detectors

1. Scope Creep Detector

Trigger: Agent touches files not in the original plan or routing decision.

How it works:

1. At task start, the routing decision lists expected files/directories
2. After each edit, compare touched files against the plan
3. If files touched exceed plan by >3 files → SCOPE CREEP ALERT

Response to scope creep:

DRIFT DETECTED: Scope Creep
  Planned files: [list from routing decision]
  Actual files touched: [current list]
  Excess: [N files outside plan]

  OPTIONS:
  A) Revert to plan — undo out-of-scope changes
  B) Expand plan — update routing decision to include new files (requires justification)
  C) Escalate to CC — ask if scope expansion is warranted

Config: .agents/config.toml [anti_drift.signals] scope_creep_threshold = 3

2. Error Cascade Detector

Trigger: 2+ consecutive errors/failures in the same task.

How it works:

1. Track each execution step's success/failure
2. If 2 consecutive steps fail → ERROR CASCADE ALERT
3. This prevents the "keep trying the same thing" anti-pattern

Response to error cascade:

DRIFT DETECTED: Error Cascade
  Failed step 1: [description + error]
  Failed step 2: [description + error]

  MANDATORY ACTIONS:
  1. STOP executing. Do not attempt fix #3.
  2. Switch to alternative approach (BRAIN_LOOP Step 4 alternatives)
  3. If no alternatives exist, generate them NOW
  4. If 3 total approaches have failed → ESCALATE TO CC

Config: .agents/config.toml [anti_drift.signals] error_cascade_limit = 2

3. Time Overrun Detector

Trigger: Task is taking >2x the estimated time.

How it works:

1. At routing, estimate task duration based on complexity tier:
   • TRIVIAL: 2 min | SIMPLE: 10 min | MODERATE: 30 min | COMPLEX: 60 min | ARCHITECTURAL: 120 min
2. Track elapsed time from task start
3. If elapsed > 2x estimate → TIME OVERRUN ALERT

Response to time overrun:

DRIFT DETECTED: Time Overrun
  Estimated: [X minutes]
  Elapsed: [Y minutes] ([Z]x overrun)
  Current step: [what's happening now]

  CHECKPOINT:
  1. Is the original approach still viable?
  2. Should we simplify scope?
  3. Is there a blocking issue that needs CC's input?
  4. Should we commit partial progress and reassess?

Config: .agents/config.toml [anti_drift.signals] time_overrun_factor = 2.0

Checkpoint Protocol

Every N task steps (default: 5, configurable in config.toml), the executing agent must pause and answer:

CHECKPOINT [step N]:
  Original intent: [1-sentence task summary]
  Current state: [what's been done so far]
  Remaining: [what's left to do]
  On track: [YES / DRIFTING — explain]
  Files touched: [count] / [planned count]
  Errors encountered: [count]

If "DRIFTING" → apply the relevant drift detector response above.

Validation Gates

Gates are hard stops between phases. Work cannot proceed until the gate passes.

Pre-Execute Gate

Before any code is written:

• Plan exists and is approved (COMPLEX+ tasks)
• Files to be modified are identified
• Agent permissions are sufficient (check config.toml [permissions])
• No conflicting work in progress (check ACTIVE_TASKS.md)

Post-Execute Gate

After implementation, before commit:

• All planned changes are complete
• No unplanned files were modified (scope check)
• Build passes (npm run build or equivalent)
• No hardcoded secrets introduced
• Changes match the original intent

Pre-Commit Gate

Before any git commit:

• Code review passed (MODERATE+ tasks)
• Commit message follows conventional format
• No .env files staged
• SESSION_LOG.md updated with what was done

Post-Deploy Gate

After pushing to remote / Vercel deploy:

• Production URL loads correctly
• No console errors on affected pages
• Webhook handlers respond correctly (if applicable)
• Mobile responsiveness verified (if UI changed)

Multi-Agent Coordination Rules

When multiple agents work on the same task (COMPLEX+):

1. One coordinator — The architect agent owns the overall plan
2. Isolated scopes — Each agent works on assigned files only
3. Sequential handoffs — Agent B waits for Agent A to finish before starting dependent work
4. Shared memory — All agents read/write to the same ACTIVE_TASKS.md
5. Conflict detection — If two agents modify the same file, flag immediately
6. Max concurrent agents: 4 (configurable in config.toml [anti_drift.max_concurrent_agents])

Integration Points

• BRAIN_LOOP Step 6 (EXECUTE): Checkpoint protocol runs during execution
• BRAIN_LOOP Step 10 (HEAL): Drift metrics logged to MISTAKES.md if drift occurred
• Task Routing Skill: Routing decision provides the baseline for scope monitoring
• Config: All thresholds and limits in .agents/config.toml [anti_drift]

Obsidian Links

• [[brain/BRAIN_LOOP]] | [[brain/AGENTS]] | [[skills/task-routing/SKILL.md]] | [[brain/CAPABILITIES]]
• [[memory/MISTAKES]] | [[memory/PATTERNS]]