create-task
Create a new Harbor task for evaluating agents. Use when the user wants to scaffold, build, or design a new task, benchmark problem, or eval. Guides through instruction writing, environment setup, verifier design (pytest vs Reward Kit vs custom), and solution scripting.
By harbor-framework · 817 installs
npx skills add harbor-framework/harbor --skill create-task
Source repository · Upstream listing
Guide the user through creating a new Harbor task end to end. Don't just dump commands —
walk them through each decision, especially around the verifier (which is usually the
hardest part).
Step 1: Scaffold the task
Useful flags:
description "..."
author "Jane Doe <jane@example.com " (repeat for multiple authors)
no pytest — skip the pytest test template (use if planning Reward Kit or custom verifier)
no solution — skip solution/ directory
metadata template path.toml — pre populate task.toml
Produces:
If the user wants a multi step task (ordered steps with per step
instructions, tests, and early stopping against a shared container), scaffold
the single step layout first, then convert to the steps/ layout described in
the Multi step tasks section below.
Step 2: Write instruction.md
This is the prompt the agent receives. Help the user write it clearly:
State the goal concretely — what file to create, what behavior to produce
Specify expected outputs — paths, formats, content
Include constraints — language, tools, approach
Don't leak the tests — describe what "done" looks like, not how you'll check it
Example (from the ssh key pair tutorial):
Step 3: Build the environment
Edit environment/Dockerfile to install dependencies the task needs. The agent works
inside this container.
For multi container setups, use environment/docker compose.yaml instead (note: most
cloud sandbox providers only support Dockerfile).
Test the environment interactively before writing the solution or tests:
This is usually where task authors realize something is missing from the Dockerfile.
Step 4: Decide how to verify
This is the most important decision. Ask the user: "How do you want to grade this
task?" Then help them pick:
Also ask: "Should the verifier run in the same environment as the agent, or in a
separate verifier environment?"
Use the default shared environment when tests need to inspect the agent's full
workspace, installed tools, or services.
Use a separate verifier environment when grading code, dependencies, API keys,
or OS requirements should stay hidden from the agent, or when verification
should run from a clean image.
For a separate verifier container, tests/ is the verifier image build context
and the image must provide /tests/test.sh (Linux) or /tests/test.bat
(Windows). Harbor copies /logs/artifacts and configured artifacts into the
verifier environment, not the agent's whole workspace.
Option A: Reward Kit (recommended for most cases)
Use when the verifier has multiple criteria, needs partial credit, uses an LLM/agent
judge, or would benefit from composable reusable checks. See the rewardkit skill.
Good fit signals:
Multiple things to check (file exists + content correct + command works)
Subjective quality dimensions (readability, correctness of prose)
Want partial credit rather than pass/fail
Want to compose built ins like file contains , command succeeds , json key equals
tests/test.sh :
Note: the package is named harbor rewardkit but the executable is rewardkit ,
hence from 'harbor rewardkit==0.1. ' rewardkit . Running
uvx harbor rewardkit directly will fail.
Then add tests/checks.py and/or tests/judge.toml . Invoke the rewardkit skill to
design the criteria.
Option B: pytest (good for deterministic unit style checks)
Use when the verification is straightforward assertion style Python. Default template if
no pytest wasn't passed.
tests/test.sh :
Example tests/test outputs.py :
Option C: Custom shell
For simple single command checks (e.g. a binary pass/fail from one command):
Reward file format (all options)
/logs/verifier/reward.txt — single number (usually 0 or 1 )
/logs/verifier/reward.json — {"accuracy": 0.95, "runtime sec": 1.2} for multiple metrics
Always use absolute paths in test.sh .
Step 5: Write the solution
Write solution/solve.sh — a script that actually solves the task. The Oracle agent runs
this to sanity check that the task is solvable and the tests pass on a correct solution.
Make it executable: chmod +x solution/solve.sh .
Step 6: Configure task.toml
Walk through the important fields:
Always populate keywords . Pick 3–8 lowercase tokens covering the domain
(language/framework/benchmark family), the verifier style ( rewardkit ,
judge grading , pytest ), and any notable hardware ( gpu ). They're surfaced in
harbor datasets list and registry search.
Network policy
Network access has three layers:
1. Baselines — set when an environment starts, restored between phases
2. Phase overrides — optional; only during agent.run() or verify()
3. Run time merges — allow environment host , allow agent host on harbor run
Field Layer When applied
[environment].network mode Baseline Agent env start; shared verifier uses this too
[verifier.environment].network mode Baseline Separate verifier env start
[agent].network mode , [steps.agent].network mode Override During matching agent.run()
[verifier].network mode , [steps.verifier].network mode Override During matching verify()
allow environment host Run time Merged into environment.extra allowed hosts → [environment] baseline
allow agent host Run time Merged into agent.extra allowed hosts → agent phase allowlist
Modes: public , no network , or allowlist with allowed hosts = ["pypi.org"]
(exact hostnames, IPv4/IPv6 address literals or CIDR ranges, or leading wildcard hostnames, when supported by the selected environment; not URLs,
ports, or paths). Omitting [environment].network mode defaults to public .
[agent] / [verifier] are optional phase overrides — only applied when set
and different from the phase baseline. Matching the baseline is a no op.
Shared verifier (default): verifier runs in the agent container; baseline is
[environment] . Separate verifier : baseline is [verifier.environment] if
set, else a copy of [environment] .
If a phase override differs from its baseline, the environment provider must
support dynamic network policy (E2B does; plain Docker does not). Prefer
environment mode = "separate" when agent and verifier need different baselines
without runtime switching:
Run time host flags for eval jobs without editing task.toml :
On a public baseline, run time host flags emit a warning and are ignored.
Examples: examples/tasks/network policy matrix/ . Full reference:
docs/content/docs/tasks/index.mdx (Network policy section).
For Reward Kit judges needing API keys:
Step 7: Verify with the Oracle agent
Oracle runs solution/solve.sh and then the verifier. Reward should be 1.0 . If it's
not, debug in this order:
1. Does solve.sh actually solve it? ( start env a i and run it manually)
2. Does the verifier correctly detect success? (check /logs/verifier/ output)
3. Are paths correct? (absolute vs relative)
4. Are dependencies installed in the Dockerfile?
Step 8: Test with a real agent (optional)
If the task is too easy (every model 1.0) or impossible (every model 0.0), consider
adjusting difficulty.
Step 9: Update README.md (always the final step)
harbor task init leaves README.md as a stub. Before wrapping up, populate it so
future humans (and agents) can understand the task without reading every file.
Include:
What the agent does — one paragraph, link to instruction.md .
Environment — base image, key installed packages, cached data, hardware
(GPU/CPU/RAM), agent timeout.
Verifier — for Reward Kit tasks, a table of reward dimensions with type
(programmatic / LLM judge / agent judge) and what each measures; how they're
aggregated.
Layout — a tree of the task directory with one line annotations.
Running — the concrete harbor run commands (Oracle + real agent), with the
right provider flag if the task needs a GPU.
Treat this as docs, not marketing — the reader wants to know what they'd need to
change to modify the task.
Multi step tasks
Use when the work splits into ordered phases that should be scored separately,
when you want early stopping between phases, or when you're testing an agent's
ability to build on its own prior work. Steps share one container; files
persist across steps.
Directory layout
Replace the task root instruction.md , tests/ , and solution/ with a
steps/ directory containing one sub directory per step:
Each [[steps]].name must match one directory name of at most 255 UTF 8 bytes,
unique after case folding and Unicode normalization. Avoid path separators,
control characters, Windows reserved characters/device names, and trailing dots
or spaces. Keep all task inputs and linked contents within the task directory;
validation permits shared links inside the task. Use regular files and directories
for shared inputs when publishing tasks.
Task level tests/ is uploaded to /tests for each step's verification, then
the step's own tests/ is layered on top (same name files win). Use this for
shared helpers.
steps/{name}/workdir/setup.sh is a reserved filename : if present, it runs
after the workdir/ upload and before the agent, as the step's agent user,
with cwd = WORKDIR. Non zero exit aborts the step and the trial. Have it
rm "$0" on its last line if the agent shouldn't see it.
task.toml
Per step overrides available: agent.timeout sec , agent.user ,
agent.network mode , verifier.timeout sec , verifier.env , verifier.user ,
verifier.network mode , verifier.environment mode , verifier.environment ,
steps.verifier.environment.network mode , healthcheck. , artifacts . Unset
fields fall back to the task level values.
Choosing a reward strategy
"mean" — aggregate signal across all steps; good for continuous
progress rewards.
"final" — last step's verifier result is the trial reward. Right when
the final step is an end to end check whose dict already represents the full
task. Caveat: if min reward triggers an early abort, "final" uses the
aborted step's result, not the intended final step.
Artifacts
Step level artifacts are collected into steps/{name}/artifacts/ after that
step's verification. Task level and trial level artifacts are collected at
every step in addition to the step level ones.
Oracle verification
harbor run p "<task path " a oracle runs each step's solution/solve.sh ,
then each step's verifier, in order. Trial reward should be 1.0 across the
aggregation strategy.
Full reference + worked example
Docs: docs/content/docs/tasks/multi step.mdx
Example task: examples/tasks/hello multi step advanced/
Special features (mention if relevant)
Network policy : Baselines on [environment] / [verifier.environment] ; phase
overrides on [agent] / [verifier] ; see Network policy under Step 6
MCP servers : Add [[environment.mcp servers]] in task.toml for agent tooling
Healthcheck : Add [environment.healthcheck] for services that need to be ready
GPU : Set environment.gpus and optionally environment.gpu types
Pre built image : Set environment.docker image instead of building from Dockerfile. You can omit environment/Dockerfile and place runtime files (configs, scripts, data) directly under environment/ ; Harbor uploads them into the container workdir when the environment starts.
Non root user : Set agent.user / verifier.user for isolation
Common pitfalls
Forgetting to write the reward file → task "passes" silently with reward 0
Using relative paths in test.sh → breaks when Harbor runs it from a different cwd
Installing the solution into the Dockerfile → agent already gets the answer
Test script leaks into instruction.md → agent sees the rubric and gaming becomes trivial
Forgetting chmod +x so