Zero Context Lab (ZCL)

ZCL helps you build better agentic tools by testing them with real agents and turning each run into structured evidence.

You run a mission through ZCL, record the final result, and get a clear breakdown of what happened:

• how many turns/actions the agent needed
• how many tokens it used (when runner usage is available)
• where retries, timeouts, or friction happened

This makes it easier to improve command design, naming, and defaults so agents complete tasks faster with fewer mistakes.

Design Contract

• Evidence comes from artifacts and traces.
• Scoring is runner-agnostic.
• Artifact shapes are deterministic and versioned.
• Captures are bounded and redacted by default.
• Operator workflows are JSON-first for automation.

Quick Install

skills.sh (agent-first):

npx skills add marcohefti/zero-context-lab@zcl

Install

Current install path (from source):

go build -o bin/zcl ./cmd/zcl
./install.sh --file ./bin/zcl
zcl version

Homebrew:

brew install marcohefti/zero-context-lab/zcl

npm:

npm i -g @marcohefti/zcl

Alternative (Go toolchain install):

go install github.com/marcohefti/zero-context-lab/cmd/zcl@latest

skills.sh:

npx skills add marcohefti/zero-context-lab@zcl

Updates

ZCL does not auto-update at runtime.

Check update status:

zcl update status --json
zcl update status --cached --json

Update explicitly via your install path:

npm i -g @marcohefti/zcl@latest
brew upgrade marcohefti/zero-context-lab/zcl
go install github.com/marcohefti/zero-context-lab/cmd/zcl@latest

Agent harnesses can enforce a minimum installed version via:

export ZCL_MIN_VERSION=0.2.0

Interactive shells get at-most-once-per-day update notices by default. Set ZCL_DISABLE_UPDATE_NOTIFY=1 to silence notices, or ZCL_ENABLE_UPDATE_NOTIFY=1 to force-enable.

zcl on skills.sh is synced via GitHub Actions: .github/workflows/skills-sh.yml.

Quick Start (Single Attempt)

1. Initialize workspace:

zcl init

2. Allocate attempt:

	zcl attempt start \
	  --suite smoke \
	  --mission hello-world \
	  --prompt "Run echo hello and finish with zcl feedback." \
	  --isolation-model native_spawn \
	  --json
	```

3. Load attempt env (pick one):

```bash
# auto-written per attempt:
source .zcl/runs/<runId>/attempts/<attemptId>/attempt.env.sh

# or explicit export from any attempt dir:
zcl attempt env --format sh <attemptDir>

# optional custom output path:
zcl attempt start --env-file .zcl/current-attempt.env --env-format sh --json ...
source .zcl/current-attempt.env

4. Run actions through a funnel:

zcl run -- echo "hello"

5. Finish with canonical outcome:

zcl feedback --ok --result "HELLO=hello"

6. Compute + validate:

zcl attempt finish --strict --json
zcl attempt explain --json

Quick Start (Suite)

Native host orchestration path (preferred when host supports native fresh session spawn):

zcl suite plan --file suite.yaml --json

Process-runner fallback path:

zcl suite run \
  --file suite.yaml \
  --feedback-policy auto_fail \
  --campaign-id smoke-campaign \
  --progress-jsonl .zcl/progress/smoke.jsonl \
  --session-isolation process \
  --json \
  -- <runner-cmd> [args...]

Artifact Layout (Default)

Root: .zcl/

.zcl/
  runs/<runId>/
    run.json
    suite.json                  (optional snapshot)
    suite.run.summary.json      (optional)
    run.report.json             (optional)
    attempts/<attemptId>/
      attempt.json
      attempt.env.sh            (ready-to-source env handoff)
      prompt.txt                (optional snapshot)
      tool.calls.jsonl          (primary evidence)
      feedback.json             (primary evidence)
      notes.jsonl               (optional)
      captures.jsonl            (optional)
      attempt.report.json       (computed)
      runner.ref.json           (optional)
      runner.metrics.json       (optional)

Command Surface

Core commands:

• zcl init
• zcl update status [--cached] [--json]
• zcl contract --json
• zcl attempt start|env|finish|explain|list|latest
• zcl suite plan|run
• zcl runs list
• zcl run
• zcl mcp proxy
• zcl http proxy
• zcl feedback
• zcl note
• zcl report
• zcl validate
• zcl expect
• zcl replay
• zcl doctor
• zcl gc
• zcl pin
• zcl enrich

For machine-readable command + artifact contract:

zcl contract --json

Operator FAQ

Find latest successful attempt for a mission:

zcl attempt latest --suite <suiteId> --mission <missionId> --status ok --json

List attempts/runs for automation dashboards:

zcl attempt list --suite <suiteId> --status any --limit 100 --json
zcl runs list --suite <suiteId> --json

Control missing feedback behavior:

# strict: missing feedback stays a hard failure
zcl suite run --file suite.yaml --feedback-policy strict --json -- <runner>

# auto_fail: synthesize canonical infra-failure feedback when runner exits early
zcl suite run --file suite.yaml --feedback-policy auto_fail --json -- <runner>

Stream live machine-readable status:

zcl suite run --file suite.yaml --progress-jsonl .zcl/progress/suite.jsonl --json -- <runner>

Canonical campaign continuity state:

zcl suite run --file suite.yaml --campaign-id <campaignId> --json -- <runner>
# writes .zcl/campaigns/<campaignId>/campaign.state.json by default

Developer Flow

Single repo gate:

./scripts/verify.sh

This runs formatting/tests/vet + contract/docs/skills checks.

Docs Map

• PLAN.md (execution checklist)
• CONCEPT.md (why + non-negotiables)
• ARCHITECTURE.md (system model + command map)
• SCHEMAS.md (exact v1 schemas and canonical IDs)
• AGENTS.md (operator workflow + builder index)
• docs/feedback-evaluation.md (feedback triage and broad-value recommendation routine)

PLAN.md is intentionally local/gitignored for operator in-flight planning.