Memory
Conversation is not durable state
Long tasks outlive a single working window. Decisions and the next safe step must survive outside chat memory.
Delivery Harness Framework / DHF Beginner Guide
What DHF does before an agent starts building.
DHF is a delivery framework for agentic engineering. It selects a governance profile, routes scoped execution, and preserves verification evidence; full recovery or handoff is conditional rather than universal.
Why it exists
Why beginners need a harness
Ambiguity
Broad requests hide decisions
Audience, scope, acceptance criteria, and domain language need to be explicit before implementation begins.
Routing
More tools do not mean better choices
The lifecycle stage determines whether the next owner is requirements, planning, development, validation, review, or handoff.
Evidence
“Done” must be checkable
A completion claim needs a fresh check, a clear outcome, the important observation, and evidence of when it ran.
Continuity
The next session must be able to resume
A durable handoff records what changed, what was verified, what is blocked, and one next safe task.
Orientation
Ask where the work is first
Recovering the current lifecycle stage prevents a resumed task from repeating work or jumping into a new direction.
Plain Definition
What DHF Does
DHF answers five questions before it claims progress: what facts were read, which lifecycle stage the work is in, which skill or helper owns the next step, how the result will be verified, and what the next safe task is.
Recover
Facts first
Read repo instructions, durable state, git status, and recent evidence before trusting chat memory.
Route
Stage-aware work
Choose requirements, planning, development, validation, review, ship, or handoff before choosing tools.
Prove
Evidence over vibes
Completion needs command, exit_code, key_output, and timestamp.
Three-layer model
Three layers keep responsibilities clear
Runtime layer
Rules and observable state
Global and repository instructions, permissions, durable evidence, and environment checks define what work is allowed and what is currently true.
Router layer
Lifecycle ownership
The router recovers state, identifies the current stage, and chooses the workflow that owns the next bounded step.
Specialist layer
Focused execution
Planning, testing, QA, security, documentation, and release specialists perform the work inside the chosen boundary.
Five-step flow
Five-step flow
This is a checklist, not mandatory ceremony. Only governed work with a matching escalation signal runs harness_recover.py, harness_env_probe.py, or harness_checkpoint.py; light does not require those lifecycle helpers.
1
Recover when escalated
Restore phase, dirty state, latest verification, and next safe task only when the governed signal requires it.
2
Clarify
If the goal, scope, vocabulary, or acceptance criteria are unclear, stop and lock requirements first.
3
Route
Select the lifecycle owner: planner, TDD, QA, security review, ship workflow, docs, or a runtime helper.
4
Verify
Run the relevant command and capture the evidence fields before saying the work is complete.
5
Handoff when escalated
Record checkpoint state only when a matching governed signal requires durable handoff.
Concrete IO
Input request -> DHF output
input request
"Improve the public DHF docs so an English reader knows where to start, and prove the links are valid."
DHF output
stage: validationcommand:python3 test_runner.pyexit_code:0key_output:[PASS] lifecycle skill routing doc discoverabletimestamp:2026-05-14T00:00:00-04:00
Glossary
Terms you will see on the next pages
Lifecycle stage
The current kind of work—such as requirements, planning, development, validation, review, ship, or handoff.
Gate
An observable condition that must pass before work is allowed to move to the next stage.
Vertical slice
A small outcome that can be implemented, checked, and accepted independently.
Feedback loop
A repeatable way to observe the problem or result before forming conclusions.
Durable handoff
A written state package that lets another session resume without relying on conversation history.
Next safe task
One bounded action that respects current scope, permissions, blockers, and verified state.
Next