Bug Description

When using a custom provider with the anthropic_messages protocol, Hermes can rewrite the configured model name by replacing . with -.

This affects custom Anthropic-compatible endpoints that expect the model ID exactly as configured by the user.

Examples:

• claude-sonnet-4.6 → claude-sonnet-4-6
• glm-4.7 → glm-4-7
• qwen3.5-plus → qwen3-5-plus

Steps to Reproduce

1. Configure a custom provider that uses an Anthropic-compatible endpoint.
2. Set its API mode / transport to anthropic_messages.
3. Configure a model name containing dots, such as claude-sonnet-4.6.
4. Send a request through Hermes.
5. Observe that the outgoing model name is rewritten with . replaced by -.

Expected Behavior

For custom providers, Hermes should send the configured model name unchanged.

If the configured model is claude-sonnet-4.6, the request should use claude-sonnet-4.6.

Actual Behavior

On the anthropic_messages path, Hermes can rewrite the model name before sending the request, replacing dots with hyphens.

As a result, custom endpoints may receive a different model ID than the one configured by the user.

Affected Component

• Configuration (config.yaml, .env, hermes setup)
• Agent Core (conversation loop, provider/runtime handling)

Messaging Platform (if gateway-related)

• N/A (CLI only)

Debug Report

Not attached yet. This was identified from source analysis and behavior inspection rather than a runtime crash. I can provide a debug report if needed.

Operating System

• macOS

Python Version

• Python 3.12.12

Hermes Version

• Hermes Agent v0.11.0 (2026.4.23)

Additional Logs / Traceback (optional)

No traceback. This appears to be a model-name normalization behavior issue.