In the programming and development community, the Claude series models from Anthropic have long been recognized as a top-tier choice for their exceptional code generation capabilities. Previously, the Claude Desktop desktop application briefly enabled Gateway mode, allowing users to access other vendors' large models via API without logging in. This "open" initiative coincided with the price reduction trend of DeepSeek V4, attracting numerous developers to integrate third-party models such as DeepSeek, GPT, and Grok into the Claude interface.

However, this flexible compatibility only lasted for about two weeks. According to recent technical tests, after updating to version 1.6259.1, the Claude desktop application has officially blocked third-party API access.

Introducing a Whitelist Mechanism to Precisely Intercept Third-Party IDs

The core change in this update is the addition of a model ID whitelist check within the Gateway mode. The system now strictly checks the model information returned by the interface, allowing only model entries named "claude" or "anthropic" to pass. This means that non-native models like DeepSeek V4, which do not meet the naming rules, can no longer be displayed or accessed within the application.

Additionally, the command-line tool Claude Code CLI (version 2.1.129) released on the same day also tightened its integration rules. Unlike the previous version, which was enabled by default, the new version has changed the gateway model discovery function to a "manual selection" mode, requiring users to set specific environment variables to enable queries.

Technical Countermeasures Intensify: Local Proxy Temporarily Becomes a "Safe Haven"

In response to this restriction, the community has begun technological countermeasures. Current monitoring shows that Anthropic's blocking measures are currently limited to model ID verification and have not yet performed in-depth detection of underlying communication protocols or model output features. Some users have already bypassed the verification by setting up local proxy servers to disguise the model IDs of third-party APIs as official names (such as mapping them to claude-sonnet-4-6).

Although these "shell-switching" solutions remain effective at this stage, industry analysts believe that given Anthropic's consistent closed-loop ecosystem approach, it is possible that detection methods will be upgraded in the future to completely block third-party model access. For developers who are used to low-cost API integration with powerful UI interfaces, seeking open-source alternatives such as OpenCode may become a new option.