Speculative Execution

Results ready before you confirm

En bref

Imaginez commander un cafe dans un bar ou le barista connait vos habitudes. Avant meme que vous ayez fini de parler, votre cappuccino est deja en preparation. Si vous changez d'avis pour un the, pas de probleme - le cafe est annule. Mais 9 fois sur 10, vous gagnez 2 minutes d'attente.

C'est l'execution speculative de PML : quand le systeme est suffisamment confiant dans ce que vous allez demander, il commence le travail avant votre confirmation. Si la prediction est correcte, le resultat est instantane. Sinon, l'execution speculative est simplement ignoree.

Ce que cela vous apporte :

  • 0ms de latence perçue : Le resultat apparait instantanement
  • Fluidite : Pas d'attente frustrante entre vos actions
  • Securite : Les operations risquees ne sont jamais speculees

The Core Feature

Speculative execution is THE differentiating feature of PML. It transforms the user experience from:

Sequential vs Speculative

How It Works

Speculative Execution Flow

Confidence Threshold

Not every action is speculated. PML uses confidence scores to decide:

Confidence Score = GraphRAG prediction × Recent success rate

Default threshold: 0.70 (configurable)

  0.50  │ Too risky - Wait for confirmation
  0.70  │ ────────── Default speculation threshold ──────────
  0.85  │ High confidence - Safe to speculate
  1.00  │ Almost certain

Adaptive Learning

The threshold adapts based on your feedback:

Action               Effect on Threshold
─────────────────────────────────────────
Accept speculation → Threshold decreases slightly (more speculation)
Reject speculation → Threshold increases (more conservative)
Modify then accept → Threshold stays stable

Target: 85% acceptance rate
Bounds: [0.40, 0.90] - Never too risky, never too conservative

Configuration: See config/speculation_config.yaml (Configuration Reference)

Safety Measures

Speculative execution has strict guardrails:

Operations Never Speculated

Operation Category Reason
delete_* File/resource deletion Irreversible
deploy_* Production deployments High impact
send_email External communication Can't unsend
payment_* Financial transactions Real money
publish_* Public releases Public visibility

These operations ALWAYS require explicit confirmation.

Resource Limits

Each speculative execution is constrained:

Limit Value Rationale
Cost < $0.10 Waste from wrong speculation stays minimal
Time < 5 seconds Quick operations only
Scope Reversible only Must be able to discard result

Sandbox Execution

Speculative executions run in isolated sandboxes:

Confirm Flow

Sandbox properties:

  • Isolated file system
  • No external side effects
  • Automatic cleanup on reject

On confirm: Merge results | On reject: Discard sandbox

Cost-Benefit Analysis

Why speculation is worth occasional waste:

Cost Decision

Scenario Wait Time Compute Waste
Without Speculation 300s/day $0
With Speculation 30s/day ~$0.50/day

Net gain: 270s saved + better flow state. Context savings ($5-10/day) >> Speculation waste ($0.50/day)

When Speculation Happens

High-Confidence Scenarios

Scenario                              Confidence    Speculate?
────────────────────────────────────────────────────────────────
You always run tests after editing     0.95         ✅ Yes
User selected "create issue" option    0.98         ✅ Yes
Similar pattern succeeded 5x today     0.91         ✅ Yes
First time using this tool             0.60         ❌ No
User manually typed different intent   0.45         ❌ No

The GraphRAG Connection

Speculation relies on GraphRAG predictions:

GraphRAG Knowledge:
  • "read_file → parse_json" sequence: 95% of the time
  • "error detected → create_issue" pattern: 88% match
  • User's recent workflow: file analysis

Combined Confidence:
  sequence_confidence × pattern_match × recency_boost = 0.92

  → Speculation triggered

Ce que cela change pour vous

Avant l'execution speculative

1. Vous demandez "Creer une issue pour ce bug"
2. PML analyse votre demande (500ms)
3. PML suggere une action (200ms)
4. Vous confirmez
5. PML execute (2-3s)
6. Resultat affiche

Total: 3-4 secondes d'attente active

Avec l'execution speculative

1. Vous demandez "Creer une issue pour ce bug"
2. PML analyse + suggere + execute en parallele
3. Vous confirmez
4. Resultat deja disponible

Total: 0 seconde d'attente apres confirmation

L'effet "magie"

Les utilisateurs de PML decrivent souvent l'experience comme "magique" :

"J'ai l'impression que PML lit dans mes pensees. Je clique sur confirmer et le resultat est deja la."

Cette sensation vient de l'execution speculative. PML ne lit pas dans vos pensees - il utilise vos patterns pour predire avec precision ce que vous allez probablement faire.

Metrics and Monitoring

PML tracks speculation performance:

Metric Description Target
Speculation Rate % of actions speculated 60-80%
Acceptance Rate % of speculations accepted >85%
Waste Rate % of compute wasted <15%
Latency Saved Time saved by correct speculation 2-5s/action

You can view these in the dashboard under "Performance → Speculation Stats".

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