[BUG] Philips Hue MCP actions fail in ChatGPT with 403 due to missing hue-application-key

When using the Philips Hue integration through Pipedream's hosted MCP server in ChatGPT, Philips Hue actions fail with 403 Forbidden because the required username prop, which is sent to the Hue API as the hue-application-key header, is not populated.
The Philips Hue account connects successfully through Pipedream OAuth, including selecting the correct Hue Bridge during authorization. The Pipedream MCP server can also be successfully connected and authenticated in ChatGPT, and the Philips Hue actions are discovered and exposed to GPT. However, when GPT invokes actions such as philips_hue-turn-light-on or philips_hue-set-light-color, the action cannot retrieve the available Hue light IDs and fails with a 403 Forbidden / missing username error.

Start by tracing the Philips Hue integration's OAuth and hosted MCP action flow, then reproduce a light action such as philips_hue-turn-light-on in ChatGPT. Check where the required username prop is passed to the Hue API and verify that the hue-application-key header is present; done means light IDs can be retrieved and actions no longer fail with 403.

Written by the indexing model from the issue text.