Parallel Execution

Skill: parallel-execution

What I do

I am the EXECUTE phase — after pre-action PREFLIGHT planning, I batch all independent tool calls into a single message. This reduces token overhead by avoiding sequential context rebuilding.

Workflow: pre-action (PREFLIGHT) → parallel-execution (EXECUTE)

When to use me

• After PREFLIGHT — batch calls marked as Parallel in the plan
• During investigation (read multiple files in one call)
• During verification (lint + test + arch-check in one call)

Core principles

1. Plan first — Use pre-action PREFLIGHT to identify independent work
2. Batch aggressively — Single message, multiple tool calls
3. Respect dependencies — Dependent tasks MUST sequence
4. Measure savings — Track parallel vs sequential cost

Parallelisation Patterns

Fan-Out Investigation

ONE question → MANY parallel reads → COMBINE results
Example: "Where is X used?" → Read files A, B, C, D in parallel
Savings: ~40-60% vs sequential

Parallel Verification

ONE change → MANY parallel checks → GATHER results
Example: After edit → lint + test + arch-check in parallel
Savings: ~50-70% vs sequential

Scatter-Gather Research

ONE bug → MANY parallel investigations → IDENTIFY root cause
Example: Bug report → check logs + read code + search issues in parallel
Savings: ~30-50% vs sequential

Token Savings Analysis

Overhead saved: Each separate call adds ~50-100 tokens of overhead.

Execution Rules

MUST Parallel (Independent)

• Reading multiple files
• Running multiple tests/checks
• Searching multiple patterns
• Fetching multiple URLs
• Creating multiple entities

MUST Sequence (Dependent)

• Write → Read (verify)
• Branch → Commit
• Build → Test
• Investigate → Fix → Verify
• Query → Process results

Integration with pre-action

1. PREFLIGHT identifies which steps are independent
2. EXECUTE batches those steps into parallel tool calls
3. Mid-chain reflection (from pre-action) reassesses after results

Anti-patterns to avoid

• ❌ Sequential calls for independent operations
• ❌ Parallelising dependent operations
• ❌ Not batching tool calls
• ❌ Ignoring parallelisation opportunities
• ❌ Not tracking efficiency gains

KB Reference

~/vaults/baphled/3. Resources/Knowledge Base/AI Development System/Skills/Workflow-Orchestration/Parallel Execution.md

Related skills

• pre-action — PREFLIGHT phase: plan before this skill executes
• token-cost-estimation — Benefits from parallel efficiency
• token-efficiency — Complementary efficiency techniques