What features would you like to see added?

I would like to request support for Claude Sonnet 4.6, released today (Feb 17, 2026).

This model should be added to both Anthropic and Google Vertex AI endpoints, utilizing the Adaptive Thinking implementation (which is already configured for Opus 4.6).

https://console.cloud.google.com/vertex-ai/publishers/anthropic/model-garden/claude-sonnet-4-6
https://platform.claude.com/docs/en/about-claude/models/overview

Required Model IDs:

• Anthropic API: claude-sonnet-4-6
• GCP Vertex AI: claude-sonnet-4-6

Configuration Requirements:

• Thinking Mode: Enable thinking: { type: "adaptive" } by default or as the primary option, similar to Opus 4.6.
• Effort Parameter: Ensure the effort parameter (Low, Medium, High) is available for this model, as budget_tokens is deprecated for Sonnet 4.6.
• Context Window: 200k tokens (Standard). Support for Preview 1M context can be enabled.

More details

Release Date: February 17, 2026
Training Data Cutoff: Jan 2026

Pricing Structure (Tiered):
The pricing for Sonnet 4.6 introduces a tiered model based on context usage that LibreChat may need to account for:

• Standard (<= 200k context): Input $3.00 / MTok | Output $15.00 / MTok
• High Context (> 200k tokens): Input $6.00 / MTok | Output $22.50 / MTok

Vertex AI Implementation Reference:
The specific implementation for Vertex AI uses the anthropic[vertex] library.

# Example provided in documentation
from anthropic import AnthropicVertex

LOCATION = "global"

client = AnthropicVertex(region=LOCATION, project_id="PROJECT_ID")

with client.messages.stream(
        max_tokens=1024,
        messages=[
            {
                "role": "user",
                "content": "Send me a recipe for banana bread.",
            }
        ],
        model="claude-sonnet-4-6"
) as stream:
    for text in stream.text_stream:
        print(text)

Which components are impacted by your request?

• endpoints/anthropic
• endpoints/googleVertexAI
• models/pricing (Needs update for the <=200k vs >200k tiered pricing structure)
• librechat.yaml (default model lists)

Which components are impacted by your request?

Endpoints

Pictures

Code of Conduct

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