Fix HTTP 406 when Accept header lacks text/event-stream#266
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omar-y-abdi wants to merge 2 commits intotadata-org:mainfrom
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Fix HTTP 406 when Accept header lacks text/event-stream#266omar-y-abdi wants to merge 2 commits intotadata-org:mainfrom
omar-y-abdi wants to merge 2 commits intotadata-org:mainfrom
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…port The upstream MCP StreamableHTTPSessionManager requires both application/json and text/event-stream in the Accept header. Standard HTTP JSON-RPC clients (e.g., Google Gemini CLI) only send Accept: application/json, causing a 406 Not Acceptable error. This adds _ensure_accept_headers() to the FastApiHttpSessionManager which appends text/event-stream to the Accept header when it is missing before delegating to the upstream session manager. This ensures standard HTTP JSON-RPC clients work out of the box with mount_http(). Fixes tadata-org#233
- Return early from the original scope reference when SSE is present (avoids copying the headers list on the happy path) - Hoist `new_headers = list(raw_headers)` before the branch to deduplicate the identical call in both if/else arms - Remove the intermediate `has_sse` variable; inline the early return
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Fixes #233
Clients sending only Accept: application/json get a 406 from the upstream MCP library because it requires text/event-stream in the Accept header.
This adds _ensure_accept_headers() to FastApiHttpSessionManager that appends text/event-stream to the Accept header before delegating to the upstream session manager. The original request scope is not mutated.
Includes 8 new tests (3 integration, 5 unit). All 130 tests pass, coverage 83.53%, ruff and mypy clean.