Support GITHUB_ACCESS_TOKEN for OAuth and PAT compatibility

[Copilot]

Summary

Add GITHUB_ACCESS_TOKEN environment variable as the preferred name, with GITHUB_PERSONAL_ACCESS_TOKEN as deprecated fallback. The old name incorrectly implied only PATs work when OAuth tokens (e.g., from VS Code) are equally valid.

Why

The environment variable name GITHUB_PERSONAL_ACCESS_TOKEN is too restrictive. OAuth tokens provisioned by IDEs work fine but the name suggests otherwise, forcing users toward manual PAT creation unnecessarily.

What changed

• cmd/github-mcp-server/main.go: Check GITHUB_ACCESS_TOKEN first, fallback to GITHUB_PERSONAL_ACCESS_TOKEN
• Error message now mentions both variables
• Documentation updated: README, server-configuration.md, all installation guides, e2e tests
• Both variables work; new one takes precedence when both set

MCP impact

• No tool or API changes

Configuration change only—no MCP protocol or tool changes.

Prompts tested (tool changes only)

N/A

Security / limits

• No security or limits impact

Uses existing token validation; only changes variable name lookup.

Tool renaming

• I am not renaming tools as part of this PR

Lint & tests

• Linted locally with ./script/lint
• Tested locally with ./script/test

Docs

• Updated (README / docs / examples)

All documentation and examples now use GITHUB_ACCESS_TOKEN. Added deprecation notice for old variable name.

Original prompt

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This section details on the original issue you should resolve

<issue_title>GITHUB_PERSONAL_ACCESS_TOKEN env var name assumes a PAT will be used</issue_title>
<issue_description>The GitHub MCP server must be spawned with GITHUB_PERSONAL_ACCESS_TOKEN as an environment variable set with a value to use in GitHub API calls.
But the very name of this environment variable specifies too much. A personal access token is an access token that is provisioned manually by the user (through https://github.com/settings/tokens). This is tedious and a 'last resort' for authorizing apps.

A far preferable way to get an access token (which presumably works for this MCP server) is to use OAuth 2.0. For example, the Visual Studio keychain can produce such a token automatically for the user. But this is not a personal access token, but rather merely an access token.

The environment variable name suggests it must be a PAT, but in fact it's just an access token that's required.

Please consider adding support for GITHUB_ACCESS_TOKEN as an environment variable, document that, and deprecate use of the old environment variable name.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes GITHUB_PERSONAL_ACCESS_TOKEN env var name assumes a PAT will be used #357

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[Copilot]

Pull request overview

This PR adds support for GITHUB_ACCESS_TOKEN as the preferred environment variable name for GitHub authentication, while maintaining backward compatibility with GITHUB_PERSONAL_ACCESS_TOKEN. The change addresses the misleading naming that suggested only Personal Access Tokens (PATs) work, when OAuth tokens from IDEs are equally valid.

Key Changes:

• Added fallback logic in cmd/github-mcp-server/main.go to check GITHUB_ACCESS_TOKEN first, then GITHUB_PERSONAL_ACCESS_TOKEN
• Updated error messages to reference both variable names
• Comprehensively updated all documentation, installation guides, examples, and test files to use the new variable name

Reviewed changes

Copilot reviewed 12 out of 13 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
cmd/github-mcp-server/main.go	Implements the environment variable fallback logic with clear precedence ordering and updated error message
e2e/e2e_test.go	Updates Docker environment variable and comments in end-to-end test setup
e2e/README.md	Updates documentation to reference the new variable name
script/conformance-test	Updates conformance test script to use new variable name
docs/server-configuration.md	Updates all configuration examples throughout the server configuration guide
docs/installation-guides/install-claude.md	Updates all Claude installation examples and commands
docs/installation-guides/install-cursor.md	Updates Docker configuration example for Cursor IDE
docs/installation-guides/install-gemini-cli.md	Updates Gemini CLI configuration examples for both Docker and binary installations
docs/installation-guides/install-windsurf.md	Updates Windsurf configuration example
docs/installation-guides/install-other-copilot-ides.md	Updates configuration examples for various Copilot-enabled IDEs
docs/installation-guides/install-antigravity.md	Updates Docker configuration example for Antigravity IDE
README.md	Updates all examples, prerequisites section, and Docker commands; adds deprecation notice for old variable name