page:recipes:mcp server:echo:response streaming

Host mcp server with Echo: streamed responses

Deploy a mcp server built with Echo on Ample using the streaming response service pattern. Compute runs the app in an isolated microVM behind a public HTTPS URL, a managed PostgreSQL 16 database is auto-provisioned and injected as DATABASE_URL. Verified on Echo: a Server-Sent Events endpoint read incrementally through the public HTTPS gateway: five one-second chunks arrived spread over time with the first within seconds (not buffered), a 70-second stream of 36 chunks completed past common 60-second idle timeouts, and a client that disconnected after two chunks was observed and recorded by the server (disconnected=true). Not separately tested: your event schema, reconnection strategy and any per-request duration ceiling beyond the 70 seconds measured; treat the mcp server-specific behavior as your application code.

Representative Queries

Resource Requirements

Infrastructure Requirements

  1. Compute
    • Status: verified
    • Summary: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.
  2. Postgres
    • Status: verified
    • Summary: Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.

Prerequisites

Workflow Steps

  1. Build and start
    CGO_ENABLED=0 go build -o app ./... then ./app on the ubuntu-24.04 template (go.sum committed for a reproducible build). The server must bind 0.0.0.0 on PORT.
  2. Implement the pattern on PostgreSQL
    The fixture's module implements streaming response service: a Server-Sent Events endpoint read incrementally through the public HTTPS gateway: five one-second chunks arrived spread over time with the first within seconds (not buffered), a 70-second stream of 36 chunks completed past common 60-second idle timeouts, and a client that disconnected after two chunks was observed and recorded by the server (disconnected=true). Copy the approach into your schema; keep migrations idempotent and run them with --release-command.
  3. Deploy
    Run the synchronous deploy once and read the result (exit 0 live, 1 failed, 2 blocked). Re-running with no change is a no-op.
    Command: ample deploy . --name --public
  4. Verify
    Fetch the live URL and the pattern self-test route(s) (/p/streaming-response-service) from the example; then run your own checks. On failure read ample logs --kind build then --kind runtime.
    Command: ample logs --kind build

Success Checks

  1. App responds on its public URL
    • Kind: http_get
    • Path: /
    • Expect: ample canary echo patterns
  2. Streaming-response-service self-test
    • Kind: http_get
    • Path: /p/streaming-response-service
    • Expect: an SSE stream: data: id=, then chunk events one interval apart (read incrementally: first chunk within seconds, chunks spread over the interval), then data: done; /status?id= reports sent=N disconnected=true|false done=true|false

Limitations

Cost Estimate

Evidence Summary

  1. Canary Run: Echo pattern fixture deployed on Ample (CGO_ENABLED=0 go build -o app ./... then ./app on the ubuntu-24.04 template (go.sum committed for a reproducible build)); checks passed for streaming-response-service and configuration-secrets. Pattern proof: a Server-Sent Events endpoint read incrementally through the public HTTPS gateway: five one-second chunks arrived spread over time with the first within seconds (not buffered), a 70-second stream of 36 chunks completed past common 60-second idle timeouts, and a client that disconnected after two chunks was observed and recorded by the server (disconnected=true).
    • Observed At: 2026-09-21T02:34:39Z
    • Implementation Revision: 1d28ae0-dirty (CLI 0.1.21)
    • Expires At: 2027-03-20T02:34:39Z
    • Scope:
      • Checks: /p/streaming-response-service
      • Pattern: pattern:streaming-response-service
      • Template: ubuntu-24.04
  2. Canary Run: The same Echo app deployed with a --release-command migration; the marker it created was readable after activation.
    • Observed At: 2026-09-20T02:43:30Z
    • Implementation Revision: 199ff1dfd52683832ae75d3f98b53a7a4bff7f96-dirty (CLI b75e104)
    • Expires At: 2027-03-19T02:43:30Z
    • Scope:
      • Pattern: pattern:streaming-response-service

Last Verified At

2026-09-21T02:34:39Z

Unknowns