fission-ai__openspec/openspec/changes/slim-root-agents-file/proposal.md

Why

The project root currently receives a full copy of the OpenSpec agent instructions, duplicating the content that also lives in openspec/AGENTS.md. When teams edit one copy but not the other, the files drift and onboarding assistants see conflicting guidance.

What Changes

• Keep generating the complete template in openspec/AGENTS.md during openspec init and follow-up updates.
• Replace the root-level file (AGENTS.md or CLAUDE.md, depending on tool selection) with a short hand-off that explains the project uses OpenSpec and points directly to openspec/AGENTS.md.
• Add a dedicated stub template so both the init and update flows reuse the same minimal copy instructions.
• Update CLI tests and documentation to reflect the new root-level messaging and ensure the OpenSpec marker block still protects future updates.

Impact

• Affected specs: cli-init, cli-update
• Affected code: src/core/init.ts, src/core/update.ts, src/core/templates/agents-template.ts
• Update assets/readmes that mention the root AGENTS.md contents to reference the new stub message.