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HTTPS Outcalls

TODO: Write content for this page.

Explain how HTTPS outcalls work at the protocol level. Cover why HTTP from a blockchain is hard (all replicas must agree on the response), the transform function mechanism for achieving consensus, cycle pricing for outcalls, response size limits, and limitations (no WebSocket, no streaming). Focus on what developers need to know to use outcalls correctly, not protocol implementation details.

  • Portal: building-apps/integrations/https-outcalls/ (overview/conceptual files)
  • Learn Hub: HTTPS Outcalls
  • guides/backends/https-outcalls — practical how-to
  • guides/chain-fusion/ethereum — EVM RPC uses outcalls
  • reference/cycles-costs — outcall pricing