put_v1_pubsub_jetstream_streams_stream

UpdateStream rewrites a stream's configuration — subjects, limits, discard — and returns the updated stream. It is a PUT: the spec sent replaces the spec held, with one reading for the enums a caller omits — an empty storage, retention or discard keeps the stream's current one, because JetStream holds storage and retention immutable and refuses a change with a 400 rather than this door pretending it took.

Arguments

tools/list declares a type and a description for each field and nothing further. A — means neither the door nor that operation constrains the field.

Call it

A tools/call carries every argument in one flat object — nothing binds to a path or a query string. Nothing above is required, so every declared argument is shown rather than a guess at which matter.

curl -X POST https://api.hanzo.ai/v1/mcp \
  -H "Authorization: Bearer $HANZO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
       "jsonrpc": "2.0",
       "id": 1,
       "method": "tools/call",
       "params": {
         "name": "put_v1_pubsub_jetstream_streams_stream",
         "arguments": {
           "discard": "<discard>",
           "maxAge": 0,
           "maxBytes": 0,
           "maxMsgs": 0,
           "retention": "<retention>",
           "storage": "<storage>",
           "stream": "<stream>",
           "subjects": [
             "<subjects>"
           ]
         }
       }
     }'

Values are the operation's own defaults and enumerated values where it declares them, and a <placeholder> where neither source declares one. maxAge, maxBytes and maxMsgs hold stand-ins that cannot be spelled that way — JSON gives a number, a boolean and a timestamp no placeholder form — so those values are this page's, not the API's. Neither the door nor the operation declares one. tools/list needs no credential; tools/call does — called without one the door answers HTTP 200 with a JSON-RPC result whose isError is set and whose text says what was missing. How to get a key →

The operation behind it

The same capability over plain HTTP is in the pubsub API reference, on https://api.hanzo.ai.

All 755 tools · The door · API reference

Generated from tools/list on https://api.hanzo.ai/v1/mcp — 833 tools captured 2026-08-01, of which 755 are documented here (the operator surface is not published) (this build read the vendored copy; the door was unreachable).