Proxy MCP completion requests through Rust gateway - #41
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Replace the fixed completion stub with real backend routing: complete now validates the request, reads the namespaced prompt name or resource URI from the reference, resolves the single owning backend, forwards the request with the prefix stripped, and returns the backend CompleteResult directly (preserving argument, context, and pagination metadata). Routing failures return a gateway routing error. The mock backend gains a complete handler that only recognizes its own backend-local references, and new integration tests cover prompt and resource argument completion plus an unrouted-reference error. Implements IBM/mcp-context-forge#5254 Signed-off-by: lucarlig <luca.carlig@ibm.com>
lucarlig
marked this pull request as ready for review
June 23, 2026 09:53
merge_capabilities omitted the completions capability, so spec-compliant clients never sent completion/complete and the new proxying was unreachable. Declare it alongside prompts/resources/tools and assert it in the prompt completion test. Signed-off-by: lucarlig <luca.carlig@ibm.com>
…e-pass-through Signed-off-by: lucarlig <luca.carlig@ibm.com> # Conflicts: # crates/contextforge-gateway-rs-lib/src/gateway/mcp_gateway.rs
Signed-off-by: lucarlig <luca.carlig@ibm.com>
dawid-nowak
approved these changes
Jul 7, 2026
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Proxy MCP
completion/completethrough the Rust gateway, replacing the fixed local completion values.completenow validates the request, reads the namespaced prompt name or resource URI from the reference, resolves the single owning backend (split_prefixed_name+resolve_backend), and forwards the request with the prefix stripped. The backendCompleteResultis returned directly, preserving the argument, context, and pagination metadata. Mirrorsread_resource/get_prompt.Implements IBM/mcp-context-forge#5254