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name: agent-harness description: "Guides DataChain bundled agent skills, knowledge-base generation, target install layouts, and data-harness workflows for coding agents." disable-model-invocation: true metadata: disco-role: operating license: Apache 2.0

Agent Harness

Use this sub-skill when the user asks how DataChain works with coding agents, how to install/uninstall/list DataChain's bundled agent skills, where target agent skill files are written, how to build or refresh dc-knowledge/, or how to use DataChain as a persistent data harness over datasets and buckets.

Trigger Phrases

Load this sub-skill for prompts about:

• installing DataChain skills for Claude, Cursor, Codex, Pi, or GitHub Copilot;
• project-local versus global DataChain skill installation;
• target skill layout, command/rule files, placeholder resolution, or safe uninstall;
• dc-knowledge/, knowledge-base snapshots, collection, enrichment, index rebuilds, stale knowledge pages, or dc-knowledge/jobs/index.md;
• agent workflows over object-storage buckets, saved datasets, cross-agent handoff, compounding work across sessions, and CAST layer planning.

First Decision

1. Skill install/layout question → read target-layouts. If the user needs a safe dry-run view of directories, use skill_layout_check.py.
2. Knowledge-base or bundled-skill behavior → read agent-skill-and-knowledge-base.
3. Data harness workflow over buckets/datasets → read workflows, then use the appropriate DataChain operating sub-skill for detailed code or query mechanics.
4. Failure diagnosis → read troubleshooting and use knowledge_base_smoke.py for a read-only dc-knowledge/ tree check.

Boundaries and Reroutes

• This sub-skill owns agent-skill packaging, datachain skill install|uninstall|list, dc-knowledge/ structure/update guidance, CAST-at-a-glance routing, and agent data-harness workflows.
• For a broad DataChain CLI command catalog, reroute to sibling sub-skill cli-and-studio.
• For DataChain SDK pipeline code patterns, UDF signatures, .save(), read_storage, or script authoring details, reroute to sibling sub-skill sdk-pipelines.
• For query expression/function details, reroute to sibling sub-skill query-engine.
• For repository maintainer policy, test matrix, release, or contribution questions, reroute to sibling sub-skill repo-development.

Safety Rules

• Do not direct the user or a future agent to open DataChain's bundled source skill files. The operational guidance needed for this area is distilled in this subtree.
• Do not mutate target agent directories while only answering a layout question; use the dry-run helper first.
• Do not edit dc-knowledge/ by hand as a substitute for regenerating it from the Dataset DB. Markdown can be read for context; regeneration should come from the DataChain knowledge workflow.
• Treat .json files under dc-knowledge/ as temporary intermediates, not as the durable knowledge surface.