Copilot Agent

GitHub Copilot is GitHub's AI coding assistant, offering multi-model support and native GitHub integration through the MCP (Model Context Protocol) server.

Prerequisites

Before using Copilot with Bloom, ensure you have:

• Active GitHub Copilot Subscription: Individual, Business, or Enterprise plan
  • Check your subscription at github.com/features/copilot/plans
  • For organization/enterprise accounts: Ask your administrator to enable Copilot access

Installation

Follow the official GitHub Copilot CLI installation guide for your platform:

• macOS/Linux: Homebrew, install script, or npm
• Windows: WinGet or npm
• All platforms: Direct binary download available

After installation, verify it works:

copilot --version

Authentication

Copilot CLI requires GitHub authentication. On first launch, Copilot will prompt you to authenticate. You can also manually authenticate:

copilot /login

Alternatively, use a fine-grained personal access token with "Copilot Requests" permission by setting the GH_TOKEN or GITHUB_TOKEN environment variable.

Configuration

Basic Configuration

# ~/.bloom/config.yaml
agent:
  defaultInteractive: copilot
  defaultNonInteractive: copilot

Model Selection

Copilot supports multiple AI models. Configure via the agent section:

# ~/.bloom/config.yaml
agent:
  defaultInteractive: copilot
  defaultNonInteractive: copilot

  copilot:
    defaultModel: claude-sonnet-4.5
    models:
      - claude-sonnet-4.5
      - claude-opus-4.5
      - gpt-5.2-codex
      - gemini-3-pro-preview

Configuration Commands

# Set copilot as default
bloom config set-interactive copilot
bloom config set-noninteractive copilot

# Set default model
bloom config set-model copilot claude-sonnet-4.5

# Discover available models from copilot CLI
bloom config models copilot --discover

# Discover and save to config
bloom config models copilot -d -s

Available models depend on your subscription and are discoverable via bloom config models copilot --discover.

Capabilities

Capability	Supported	Notes
File Read	Yes	Read files in working directory
File Write	Yes	Create and modify files
Bash/Terminal	Yes	Execute shell commands
Git Operations	Yes	Full git support
Web Search	Yes	Search for information
Web Fetch	Yes	Fetch web content
Session Resume	Yes	Continue previous sessions
Human Questions	No	Runs to completion
GitHub MCP	Yes	Native GitHub operations

Unique Features

GitHub MCP Server

Copilot has built-in access to the GitHub MCP server, enabling:

• Issue and PR management
• Repository operations
• GitHub API access without additional setup

Multi-Model Support

Choose from multiple AI providers through a single interface:

• OpenAI (GPT-4o)
• Anthropic (Claude)
• Google (Gemini)

Fine-Grained Permissions

Control tool access with --allow-tool and --deny-tool flags for security-sensitive environments.

Provider-Specific Options

Option	Type	Default	Description
model	string	(default)	Model to use (e.g., claude-3.5-sonnet)

CLI Flags Reference

When Bloom runs Copilot, it uses these patterns:

# Interactive mode
gh copilot "prompt"

# With model selection
gh copilot --model claude-3.5-sonnet "prompt"

# Resume session
gh copilot --resume <session_id> "prompt"

Troubleshooting

"gh: command not found"

Cause: GitHub CLI not installed

Solution: Install GitHub CLI using the official docs.

"Copilot extension not installed"

Cause: Missing Copilot CLI extension

Solution: Install the extension using the official docs.

"Authentication required"

Cause: Not authenticated with GitHub

Solution:

# Check auth status
gh auth status

# Login if needed
gh auth login

"Copilot access denied"

Cause: No active Copilot subscription

Solution:

• Verify your GitHub account has Copilot access
• Check subscription status at github.com/settings/copilot
• For organization accounts, check with your admin

"Model not available"

Cause: Requested model not in your subscription tier

Solution:

• Check available models for your subscription
• Use a different model
• Contact GitHub support for model access

Best Practices

For GitHub-Heavy Workflows

1. Use Copilot when working with GitHub issues and PRs
2. Leverage the GitHub MCP for repository operations
3. Use multi-model support to pick the best model for each task

Model Selection Guidelines

Task Type	Recommended Model
Code generation	gpt-4o
Complex reasoning	claude-3.5-sonnet
Fast iterations	gpt-4o-mini

Security Considerations

For sensitive environments:

# Restrict tool access
gh copilot --deny-tool bash "prompt"

Example Session

# Start interactive session
bloom enter

# Copilot will:
# 1. Use its multi-model capabilities
# 2. Access GitHub MCP for repo operations
# 3. Execute to completion (no human questions)

Comparison with Claude

Aspect	Copilot	Claude
Human Questions	No	Yes
GitHub Integration	Native MCP	Via tools
Model Choice	Multiple	Anthropic only
Progress Tracking	Basic	TodoWrite

Use Copilot when:

• Working heavily with GitHub repos, issues, and PRs
• Want to use non-Anthropic models
• Need fine-grained permission control

Use Claude when:

• Need human-in-the-loop capabilities
• Want TodoWrite progress tracking
• Prefer Anthropic's models