Add Claude Opus 4.6 model support

[Copilot]

Adds missing Claude Opus 4.6 models to token estimators and pricing configuration.

Changes

• tokenEstimators.json: Added claude-opus-4.6 and claude-opus-4.6-(fast-mode)-(preview) with 0.24 character-to-token ratio
• modelPricing.json: Added both models with $5.0/$25.0 input/output costs per million tokens
  • Base model: multiplier 3 (standard premium tier)
  • Fast-mode preview: multiplier 9 (promotional pricing Feb 7-16, 2026)
• Updated metadata.lastUpdated to 2026-02-09

Both models now align with existing Claude model patterns and GitHub Copilot's supported models documentation.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• www.anthropic.com
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node /home/REDACTED/work/_temp/ghcca-node/node/bin/node --enable-source-maps /home/REDACTED/work/_temp/copilot-developer-action-main/dist/index.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

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This section details on the original issue you should resolve

<issue_title>🤖 Action Required: Update Copilot Supported Models</issue_title>
<issue_description>### 🚨 Missing Models in tokenEstimators.json
The following models are listed in the GitHub Copilot documentation but are missing from src/tokenEstimators.json:

• claude-opus-4.6
• claude-opus-4.6-(fast-mode)-(preview)

💰 Missing Models in modelPricing.json

The following models are listed in the GitHub Copilot documentation but are missing from src/modelPricing.json:

• claude-opus-4.6
• claude-opus-4.6-(fast-mode)-(preview)

Action Required:
Please update the JSON configuration files with the latest models.

Source: GitHub Copilot Supported Models</issue_description>

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

• Fixes 🤖 Action Required: Update Copilot Supported Models #191

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