feat(virtual-mcp): auto-adopt MCP server prompt as agent instructions#3164
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feat(virtual-mcp): auto-adopt MCP server prompt as agent instructions#3164
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When a virtual MCP agent has no metadata.instructions set, automatically resolve the system prompt from the connected MCP server's named prompts. Resolution order: 1. metadata.instructions (explicit, wins always) 2. Prompt whose name matches the agent title slug (e.g. "CEO Agent" → "ceo") 3. First available prompt from connected MCPs 4. undefined (no instructions) This allows MCP servers to own their system prompt in code (prompt.md) without requiring manual copy-paste into the studio database. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Summary
metadata.instructionsset, the server now automatically resolves the system prompt from the connected MCP server's named promptsmetadata.instructionsif explicitly set, (2) prompt matching agent title slug, (3) first available prompt, (4)undefinedmetadata.instructionsalways winsMotivation
MCP servers should own their system prompt in code (e.g.
prompt.md). Previously, there was no bridge between a server's declared prompt and the studio'smetadata.instructionsfield — requiring manual copy-paste that was never done. This change closes that gap automatically.Test plan
metadata.instructionsset → still uses it, no changemetadata.instructions, connected MCP has a prompt named"ceo"(matches title "CEO Agent") → uses that prompt as instructionsmetadata.instructions, connected MCP has prompts but none match → uses first availablemetadata.instructions, connected MCP has no prompts → falls through gracefully,undefined🤖 Generated with Claude Code
Summary by cubic
Automatically uses the connected MCP server’s named prompt as the agent’s system instructions when a virtual MCP agent has no
metadata.instructions. This removes manual copy-paste and keeps agents aligned with serverprompt.md.metadata.instructions> prompt matching agent title slug (lowercased, alphanumeric) > first available prompt > undefined.instructionstocreateServerFromClient; existing behavior unchanged.Written for commit f447f7b. Summary will update on new commits.