- quickstart.md: Add Anthropic to the provider comparison table
- configuration.md: Add Anthropic to provider list table, add full
'Anthropic (Native)' section with three auth methods (API key,
setup-token, Claude Code auto-detect), config.yaml example,
and provider alias tip
- environment-variables.md: Add ANTHROPIC_API_KEY, ANTHROPIC_TOKEN,
CLAUDE_CODE_OAUTH_TOKEN to LLM Providers table; add 'anthropic'
to HERMES_INFERENCE_PROVIDER values list