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C14 Advanced Design

Agent Harness Map

Choose a runtime, repository contract, or orchestrator

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The Four Layers

LayerResponsibilityDoes not replace
ModelProposes text and tool callsPermission and recovery
Runtime harnessRuns the loop and toolsRepository contract
Repository harnessInstructions, state, verificationRuntime loop
OrchestratorCoordinates runtimes and sessionsEach runtime’s decisions

An orchestrator can launch several runtimes without owning their loops. A repository can improve its contract without changing runtime.

Choose in the Right Order

  1. Define the task and acceptable autonomy.
  2. Select a runtime that owns the required loop.
  3. Write the repository contract: instructions, pass criteria, verification.
  4. Add an orchestrator only when coordination, isolation, or recovery across tasks requires it.

Four Sources, Four Uses

SourceUsed toLimit
Strict comparisonIdentify runtimesNot a universal ranking
Orchestrator tableCompare coordinationNot a runtime
Best of Agent HarnessesExplore 160 projects, 12 categories2026-08-23 snapshot
agent-harnesses.jsonRead provenance and evidenceunknown is not none

Short Trial, Traceable Verdict

Compare two or three candidates on real tasks in separate worktrees. Measure human verdict, interventions, plan drift, wall time, accepted-task cost, recovery, and setup friction.

Links: Agent Harness Map · Agent Harness Engineering · Agent Tools · Glossary

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