Harness
Tools, memory, and control rules that help a model perform tasks.
What is a harness?
A model processes input and produces a response. The harness connects the model to tools, memory, and control rules. It can call the model repeatedly to perform a task. Agent runtimes such as Claude Code and Cursor provide a harness. ClawMetry shows their recorded activity. Use the links below to inspect each part. (Read about harness engineering)
πŸ” The loop
An agent can read input, choose an action, use a tool, and check the result. This sequence can repeat until the agent finishes or reaches a limit.
Watch it live in Activity β†’
πŸ”§ Tools
Tools let an agent read or edit files, run code, search the web, and call services. The available tools depend on the runtime and its permissions.
See its tools β†’
πŸ“š Memory
A harness can save information from earlier sessions. It can supply this information to the model in a later session.
Read its memory β†’
πŸͺŸ Context
A model can process a limited amount of text at once. The harness manages that text and can remove older information.
See context usage β†’
πŸ“¦ Sandbox
A sandbox limits the files, network connections, and other resources that agent code can access. The limits depend on its configuration.
Check its sandbox β†’
🚦 Guardrails
Rules define which actions an agent can take and which actions need approval. Examples include file deletion and spending limits.
Review approvals β†’
🀝 Teamwork
An agent can give parts of a task to other agents. It can then combine their results.
See who spawned whom β†’
πŸ’¬ Interfaces
A runtime can provide access through a terminal, a browser, or a messaging service such as Telegram or Slack.
Follow the message flow β†’
Is this repo ready for an agent?
Agents get stuck on repos that do not explain themselves. This is what yours tells them.
Scanning the repo…
What this runtime uniquely exposes, beyond the generic tabs:
Loading harness view…