Open-source harness
Free
Apache-2.0; provider/infrastructure fees separate
- Included scope
- CLI/MCP; contract; worktrees; verification evidence; dashboard/plugins
HAR
● Identity checkedCoding-agent isolation and verification harness · Official-source review 2026-10-09
HAR coordinates coding workflows through a repository-owned harness contract, isolated worktrees and launch/verify/teardown stages. Its CLI and MCP expose project checks and evidence artifacts, while Mission Control tracks runs, validations and repositories.
- Category
- Coding-agent isolation and verification harness
- Free access
- Apache-2.0 software is free and open source; underlying agents, models and infrastructure retain their own costs.
- API access
- CLI and MCP support discovery, session control, verification and evidence; plugins add framework-specific verification stages.
Is HAR right for you?
A good fit for
Relevant to developers managing consistent project checks and reviewing what actually ran for an agent change.
Before you choose
Works with Claude Code, Cursor, Codex and MCP agents according to the repository. Isolation includes slot-specific ports/databases where configured, not automatically proven security isolation. Deterministic validation runs the project checks specified by the contract; it does not prove comprehensive test coverage or bug-free output. Tree-hash evidence and commit gates require setup and exact version inspection. Plugin commands can execute local tests/services. Hardware/OS requirements and hosted support tariffs are not established. No package, slot, dashboard or verification stage was run.
Workflow and handoff
Use a disposable repository, inspect launch/verify/teardown commands and check evidence against the exact modified tree before accepting a change.
Pricing and practical limits
Works with Claude Code, Cursor, Codex and MCP agents according to the repository. Isolation includes slot-specific ports/databases where configured, not automatically proven security isolation. Deterministic validation runs the project checks specified by the contract; it does not prove comprehensive test coverage or bug-free output. Tree-hash evidence and commit gates require setup and exact version inspection. Plugin commands can execute local tests/services. Hardware/OS requirements and hosted support tariffs are not established. No package, slot, dashboard or verification stage was run.
Review method
Official product evidence reviewed on 2026-10-09; product artwork inspected visually. No hands-on vendor application test was performed. Application performance, security claims and plan enforcement were not independently tested.
What it can do
Features & capabilities
Unknown is different from unavailable. Each fact carries its own evidence.
| Capability | Value | Evidence | Checked |
|---|---|---|---|
| Product workflow | HAR coordinates coding workflows through a repository-owned harness contract, isolated worktrees and launch/verify/teardown stages. Its CLI and MCP expose project checks and evidence artifacts, while Mission Control tracks runs, validations and repositories. | Facts sourced | 2026-10-09 |
| Pricing and restrictions | Works with Claude Code, Cursor, Codex and MCP agents according to the repository. Isolation includes slot-specific ports/databases where configured, not automatically proven security isolation. Deterministic validation runs the project checks specified by the contract; it does not prove comprehensive test coverage or bug-free output. Tree-hash evidence and commit gates require setup and exact version inspection. Plugin commands can execute local tests/services. Hardware/OS requirements and hosted support tariffs are not established. No package, slot, dashboard or verification stage was run. | Facts sourced | 2026-10-09 |
Understand the total cost
HAR pricing & plans
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Frequently asked questions
Was the application hands-on tested?
No. This listing is based on dated official-source evidence and a visual artwork check. Unconfirmed costs and restrictions are identified explicitly.
What is HAR used for?
HAR coordinates coding workflows through a repository-owned harness contract, isolated worktrees and launch/verify/teardown stages. Its CLI and MCP expose project checks and evidence artifacts, while Mission Control tracks runs, validations and repositories.
Does HAR have a free plan?
Apache-2.0 software is free and open source; underlying agents, models and infrastructure retain their own costs.. This record lists ongoing free access; check the plan limits before starting.
How much does HAR cost?
No paid monthly price is listed; this record treats the product as free to start. See the plan cards for entitlements, billing commitments and seat minimums.
Can I use HAR through an API?
CLI and MCP support discovery, session control, verification and evidence; plugins add framework-specific verification stages.. API access and subscription access may have different terms; consult the linked sources.
What should I check before choosing it?
Works with Claude Code, Cursor, Codex and MCP agents according to the repository. Isolation includes slot-specific ports/databases where configured, not automatically proven security isolation. Deterministic validation runs the project checks specified by the contract; it does not prove comprehensive test coverage or bug-free output. Tree-hash evidence and commit gates require setup and exact version inspection. Plugin commands can execute local tests/services. Hardware/OS requirements and hosted support tariffs are not established. No package, slot, dashboard or verification stage was run.
Price history
No retained pricing changes yet. A current price alone does not establish a historical trend.
How this profile is supported
Official product information
Current official product source read individually; product artwork inspected visually.
Read original source ↗Pricing review
Official product page reviewed for disclosed costs; unverified prices and allowances are identified in the listing.
Read original source ↗Facts apply to the named version and check date. Send a sourced correction if something changed.