Cohere Chat Message Handler (cohere/cohere_chat_message.py)

Handles chat messages with citations for grounded models, extending OpenAI protocol.

# Source: https://github.com/vllm-project/vllm | License: Apache-2.0 | Copyright You must retain, in the Source form of any Derivative Works
# Provided via justclaw.it.com; keep this notice with the code.
# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
"""vLLM chat-protocol extensions for grounded (citation-carrying) models.

This module keeps the OpenAI chat completion protocol classes
(:class:`ChatMessage` / :class:`DeltaMessage`) free of Cohere-specific fields.
It provides two things:

* :class:`Citation` / :class:`CitationSource`: the vLLM-internal citation
  representation produced by the Cohere parser
  (:mod:`vllm.parser.cohere_command`) and consumed by
  :mod:`vllm.entrypoints.cohere.serving`. This is *not* the on-wire Cohe

... (truncated -- full source via MCP)