Build with AI

This documentation, and this API, are built to be read by a model as well as by you. Two of the three things on this page work right now with nothing installed.

The whole site as text

Every page here is also served as Markdown — the same words, no markup — at the page's own address with .md on the end. And llms.txt is the index of all of them.

Shell

# The index: every page, with a sentence saying what is on it.
curl -s https://voice.sphoro.com/docs/llms.txt

# One page, as plain Markdown.
curl -s https://voice.sphoro.com/docs/agents.md

Paste one into a model, diff them between releases, or point a coding assistant's fetch tool at them. Nothing needs to be installed and no credential is required.

The API as a machine-readable description

Shell

curl -s https://voice.sphoro.com/openapi.json
curl -s https://voice.sphoro.com/openapi.yaml

Generated by the running server, so it describes the deployment you are actually talking to rather than a snapshot somebody exported. Most code generators take it directly, and most coding assistants will read it if you hand them the URL. See API reference.

Give an assistant both. The OpenAPI document tells it which fields exist; the Markdown pages tell it which combinations are sensible. On its own, the schema will happily produce an agent with a keypad map, no greeting, and nothing to read the menu out.

The MCP server

Sphoro Voice speaks the Model Context Protocol, which gives a coding assistant real hands on your account: it can create agents, place and inspect calls, manage knowledge bases, test post-call extraction, build and validate journeys, inject events into live flows, and read these docs — with the same API key you would use yourself.

The MCP server is a binary provided with your account. Ask us for the build for your platform. Once you have it, point any MCP client at it with your key in the environment — the client's own documentation covers how to add a server.

Roughly fifty tools, in the shape of the API rather than a reduction of it:

Area	What the assistant can do
Agents	Create, read, update, delete; list the templates; extract a persona from one.
Calls	Start one, read it, fetch the transcript, end it, inject an event into a live flow.
Knowledge	Create a base, ingest text or a URL, search it, list and delete.
Journeys	Create, save and validate a draft, publish it, start an execution, read one, cancel it.
Campaigns	Create, add contacts, start, pause, resume, cancel, read the report.
Post-call	Test an extraction against a transcript without placing a call.
Webhooks	Create an endpoint, list them, send a test delivery.
Compliance	Check a number, add a suppression.
Analytics	Read the overview.
Docs	Search and fetch these pages, so it answers from the current version rather than from training data.

Which turns a session into: "Create a Hindi-first collections agent that verifies date of birth before naming the amount, then test-call my number", or "Why did call call_8b21… end so fast?", or "Add an extraction for whether the caller agreed to the plan, and try it on the last three transcripts."

Skills

Task-shaped instructions for a coding assistant — the method rather than the hands. The MCP server lets an assistant call the API; the skills tell it what a good agent body looks like, how to write an extraction that answers reliably, and which field to check for each symptom.

Skill	Teaches
Authenticating	Base URLs, keys, and what a 401, 403 or 429 actually means.
Creating an agent	The body end to end: languages, conversation settings, post-call, tools, modes.
Making a call	Placing and following one; variables, compliance, end reasons.
Inbound setup	Pointing a number at an agent, menus, capacity.
Post-call extraction	Designing fields that come back right, and testing them.
Building a flow	Nodes, edges, expressions, capture, injected events.
Building a journey	Call, branch, wait, retry, message; drafts and versions.
Prompt writing	The structure, and the rules for text that is read aloud.
Debugging calls	Symptom to field: end reasons, latency, barge-in, flows, webhooks.
Webhooks	Subscribing, verifying signatures, retries, dedupe.
Campaigns and compliance	Lists, pacing, suppression, consent, calling windows.

The skills pack is distributed with your account alongside the MCP server. Ask us for it.

What to tell an assistant first

With no tooling at all, this is usually enough to get a useful first draft:

Read https://voice.sphoro.com/docs/llms.txt and then the pages it lists for agents,
prompting and post-call. The API description is at https://voice.sphoro.com/openapi.json.

Then write me a POST /v1/agents body for an outbound appointment-reminder
agent that speaks Hindi first and English second, leaves a voicemail message,
and extracts whether the appointment was confirmed.

Have it place the first call to your own number. An assistant with an API key and a phone number is an assistant that can ring a stranger. Every example on this site dials a number you control, for that reason.