Teach an agent a fact (there is no memory endpoint over REST)

The web Architect has a create_memory_entry action for ad-hoc, agent-global facts. Over the ConvAI REST API there is NO memory endpoint. Say this plainly to the user rather than implying you saved a memory. Instead, persist the fact one of two durable, branch-scoped ways below (host https://api.elevenlabs.io, header xi-api-key: $API_KEY; you need $AGENT_ID and $BRANCH_ID).

First, sanity-check the request

• Confirm the correction is scoped and factual: a discrete fact or rule ("In v3, only the Stability slider is supported"), not a broad behavioral change. Broad, recurring, or procedural changes belong in the system prompt or a new procedure, not a one-off fact.
• Confirm the fact genuinely cannot come from a crawled knowledge base (which can re-sync) or an API call (which stays current). If it can, prefer those sources.
• If the request is a broad behavioral change, escalate to editing the system prompt or creating a procedure instead.

Option A: a durable fact in the system prompt

Add the fact as a short, self-contained line the agent can recall verbatim. Read the current prompt scoped to the branch, append the line, and PATCH the whole string back:

• Read: GET /v1/convai/agents/$AGENT_ID?branch_id=$BRANCH_ID, take conversation_config.agent.prompt.prompt.
• Write: PATCH /v1/convai/agents/$AGENT_ID?branch_id=$BRANCH_ID with {"conversation_config":{"agent":{"prompt":{"prompt":"<full edited prompt>"}}}}.

This commits to the branch HEAD and returns a new version. Keep the fact short so it does not bloat the prompt.