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This guide covers the move of @outputai/http into @outputai/core. The package is no longer published: its API now lives at @outputai/core/http, with the same exports and behavior. Two smaller breaks come with it: ky and undici are now peer dependencies of @outputai/core, and sendHttpRequest() parses some response bodies differently. Separately, the worker no longer sets defaults for two workflow concurrency variables, and one telemetry field is renamed. See Worker defaults and telemetry.

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What changed

  • @outputai/http is replaced by the @outputai/core/http subpath. outputFetch, createKyClient, addRequestCost, and the ky and undici re-exports are unchanged.
  • @outputai/output no longer depends on @outputai/http.
  • ky (>=2 <3) and undici (>=8 <9) are peer dependencies of @outputai/core.
  • Tracing.Attribute.HTTPRequestCount and Tracing.Attribute.HTTPRequestCost moved from @outputai/core/sdk/runtime to @outputai/core/http as HTTPRequestCount and HTTPRequestCost. The http:request:count and http:request:cost trace attributes are unchanged.
  • sendHttpRequest() returns XML, form-urlencoded, and JavaScript response bodies as text instead of base64, and returns empty or invalid JSON bodies as raw text instead of throwing.
  • With OUTPUT_TRACE_HTTP_VERBOSE on, HTTP request and response bodies in trace files are parsed the same way as sendHttpRequest(). Multipart bodies are stored as base64.

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Migration steps

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Update imports

Replace every import of @outputai/http with @outputai/core/http, including module mocks in tests:

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Remove the dependency

Delete @outputai/http from dependencies, devDependencies, and peerDependencies in package.json. If your project depends on @outputai/core directly rather than through @outputai/output, bump it to 0.16.0.

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Install the peer dependencies

npm 7+ and pnpm install peer dependencies automatically. With other package managers, or if your install reports missing peers, add them yourself:
If your project already depends on ky or undici, make sure the versions fall in the supported ranges.

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Update trace attribute imports

Code that referenced Tracing.Attribute.HTTPRequestCount or Tracing.Attribute.HTTPRequestCost should import them from @outputai/core/http:
To attach a cost to an HTTP request, keep using addRequestCost() from @outputai/core/http.

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Re-check sendHttpRequest() response bodies

This only affects calls with responseOptions.includeBody: true: Remove any base64 decoding of those content types. If you relied on the error to detect a bad JSON response, check whether body is a string instead.

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Re-check trace file readers

If you parse trace files recorded with OUTPUT_TRACE_HTTP_VERBOSE on, request and response bodies now follow the table above, and multipart request bodies are base64 strings.

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Worker defaults and telemetry

No code changes are needed, but the worker behaves differently if you never set its concurrency variables, and one telemetry field is renamed.

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Workflow concurrency defaults

The worker no longer sets defaults for these two variables. When they are unset, @temporalio/worker applies its own: The cache size is (heap limit in MiB - 200) * 600 / 1024, with a minimum of 10. With --max-old-space-size=4096 that is about 2,400 cached workflows. The formula assumes roughly 600 cached workflows per GB of heap, so if your workflows hold large inputs, outputs, or step results, set TEMPORAL_MAX_CACHED_WORKFLOWS explicitly. If you relied on 200 concurrent workflow tasks, set TEMPORAL_MAX_CONCURRENT_WORKFLOW_TASK_EXECUTIONS=200. Keep it at or below TEMPORAL_MAX_CACHED_WORKFLOWS. The resolved values are logged at startup in the Worker sizing record, as maxCachedWorkflows and workflowTaskSlots.

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New startup warnings

After the Worker sizing record, the worker logs a warning in either or both of these cases, each with the values it compared: A project that only set TEMPORAL_MAX_CACHED_WORKFLOWS below 40 will now see the second warning, because task executions default to 40. See Memory and Isolates. A Dockerfile copied from an earlier version of the Railway or Render guide sets --max-old-space-size-percentage=80, which triggers the first warning because the worker runs two isolates by default. Those guides now use 40.

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Telemetry field rename

If you enable OUTPUT_WORKER_TELEMETRY_INTERVAL_MS and parse the periodic Worker log, memory.constrainedMemory is now memory.memoryLimit. The old field reported process.constrainedMemory() directly, which returns a sentinel near 2^64 when the process has no memory limit. memoryLimit reports the container’s limit, or the machine’s total memory when there is none. Two fields were added to the same block: memory.nonMainHeap (rss - heapUsed) and memory.heapSizeLimit.

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Checklist

  • Replace @outputai/http imports and mocks with @outputai/core/http, and remove the dependency.
  • Install ky@2 and undici@8 if your package manager does not install peer dependencies.
  • Import HTTPRequestCount and HTTPRequestCost from @outputai/core/http.
  • Remove base64 decoding of XML, form-urlencoded, and JavaScript response bodies from sendHttpRequest().
  • Set TEMPORAL_MAX_CACHED_WORKFLOWS and TEMPORAL_MAX_CONCURRENT_WORKFLOW_TASK_EXECUTIONS explicitly if you relied on the old defaults or your workflows hold large state.
  • Lower --max-old-space-size-percentage to 40 if your Dockerfile uses the earlier Railway or Render value of 80.
  • Rename memory.constrainedMemory to memory.memoryLimit in anything that parses worker telemetry.