Add setup instructions and additional tools for Supabase database administrator agent

[stephschofield]

Pull Request Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• My contribution adds a new instruction, prompt, or chat mode file in the correct directory.
• The file follows the required naming convention.
• The content is clearly structured and follows the example format.
• I have tested my instructions, prompt, or chat mode with GitHub Copilot.
• I have run npm start and verified that README.md is up to date.

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Description

The Supabase Database Administrator agent fills a specialized niche for Supabase-specific database development and administration.

1. MCP Server Integration Pioneer

• One of the first agents demonstrating comprehensive integration with an MCP (Model Context Protocol) server
• Shows how to leverage 20+ specialized MCP tools for real-time database operations
• Provides a clear template for other MCP-based agents

2. Production-Ready Database Management

• Goes beyond basic SQL assistance to include enterprise concerns:
  • Row Level Security (RLS) policy design and auditing
  • Migration management with safety protocols
  • Cost estimation and confirmation workflows
  • Security vulnerability assessment frameworks
  • Performance optimization strategies

3. Guided Onboarding Workflow

• Includes a sophisticated initial project check that prevents assumptions
• Handles three user scenarios: existing project, new project creation, or no-database mode
• Walks users through complete MCP server setup with exact configuration

4. Dual-Mode Operation

• Supabase Mode: Full database operations via MCP
• JSONL Mode: File-based alternative for prototyping without infrastructure
• Provides migration paths from JSONL to Supabase when users are ready

5. Security-First Approach

• Comprehensive security review framework with checklists
• Templated RLS policies, secure functions, and audit logging
• Risk-tiered recommendations (Critical/High/Medium/Low)
• Real-world patterns for preventing SQL injection and data exposure

6. Domain Expertise Embodiment

• Specialized knowledge of PostgreSQL, Supabase platform specifics, and database security
• Not a generic database agent—deeply tailored to Supabase's ecosystem and best practices
• Includes Supabase-specific extensions (pg_vector, PostGIS, pg_cron)

7. Developer Experience Focus

• TypeScript type generation support
• Clear cost transparency before creating billable resources
• Migration safety protocols (test locally first, reversible changes)
• Explicit confirmation for destructive operations

Gap It Fills

This agent addresses developers who:

• Build applications on Supabase (a growing PostgreSQL-based BaaS platform)
• Need expert guidance on RLS policies (a Supabase strength but complex feature)
• Want to leverage Supabase's MCP server for agent-assisted database work
• Require security auditing capabilities for their database schemas
• Are exploring Supabase but need hand-holding through setup

Unlike generic database or SQL agents in the repository, this agent:

• Requires external setup (MCP server) but provides much deeper capabilities
• Operates as a specialized consultant rather than a general assistant
• Includes operational workflows (cost confirmation, migration safety) beyond just code generation
• Bridges the gap between development and database administration roles

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Type of Contribution

• New instruction file.
• New prompt file.
• New chat mode file.
• New collection file.
• Update to existing instruction, prompt, chat mode, or collection.
• Other (please specify):

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Additional Notes

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By submitting this pull request, I confirm that my contribution abides by the Code of Conduct and will be licensed under the MIT License.

[Copilot]

Pull request overview

This PR adds a comprehensive Supabase Database Administrator agent that provides expert-level assistance for Supabase database development and administration, demonstrating sophisticated MCP server integration patterns.

Key changes:

• New specialized agent with 20+ MCP tools for Supabase operations
• Dual-mode operation supporting both Supabase MCP server and file-based JSONL storage
• Production-ready features including RLS policy management, security auditing, and migration workflows

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
agents/supabase-dba.agent.md	New agent file with comprehensive Supabase DBA capabilities, including setup instructions, security frameworks, and operational guidelines
docs/README.agents.md	Added entry for Supabase Database Administrator agent to the agents catalog
docs/supabase-dba-agent-contribution.md	Detailed contribution analysis documenting the agent's value proposition, architecture, use cases, and comparison with other database agents

[stephschofield]

Hi there, I don't have permissions to rerun the CodeQL scans in actions but all other checks have passed and should be ready for review.

[codemillmatt]

Thanks @stephschofield for this! We don't have any docs on how to use individual agents, instructions, etc. So I'd like to get @aaronpowell 's opinion on what direction to take here.

[codemillmatt]

@aaronpowell - how do you want to handle documentation for individual agents?