Cumuluslabs Cumulus Talos API
40
AI ReadinessNon-Ready (F)40/100
Official vendor OpenAPI document · agent-readyCommunicationsVoice Telephonybearer105 EndpointsREST
For Agents
Build and run AI voice agents over the phone: start calls, stream run events, and pull recordings, transcripts, and analysis. Provision numbers and SIP trunks, configure voices, and evaluate agents with test suites and scored test runs.
Use for: I want to build a voice agent and publish it, Start a phone call run with my agent, Get the transcript of a completed call, Import a phone number for outbound calls
Not supported: Does not handle video conferencing, email, or SMS marketing campaigns. Use for building, running, and evaluating voice agents over the phone only.
The Cumulus Talos API builds, runs, and evaluates conversational voice agents that operate over the phone and the web. It versions agent drafts and publications, starts runs that place or take calls, and returns recordings, transcripts, and post-run analysis for each one. Telephony management covers imported phone numbers, SIP trunks, and outbound call limits, while test suites and scored test runs let you regression-test an agent before publishing a new version.
Install Jentic One Beta
Connect the Cumulus Talos API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Cumulus Talos API, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.
1
Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fcumuluslabs.io%2Fcumuluslabs" | sh2
Step 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fcumuluslabs.io%2Fcumuluslabs" | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
Capabilities
What an agent can do with Cumulus Talos API.
Build conversational voice agents and publish versioned revisions
Start phone and web runs, then stream run events until the call completes
Retrieve call recordings, transcripts, and post-run analysis
Provision phone numbers and connect SIP trunks for outbound and inbound calls
Evaluate agent behaviour with test suites, test runs, and scored trials
Configure speech models and preview voices before publishing
Track usage, budgets, and rate cards across runs
Use Cases
Patterns agents use Cumulus Talos API for, with concrete tasks.
★ Agent-Operated Voice Calls
An AI agent connected through Jentic can configure and run voice calls end to end: it creates and publishes an agent, starts a run against a provisioned phone number, streams run events while the call is live, and pulls the recording and transcript once it ends. Cumulus Talos runs are asynchronous, so the agent subscribes to events or polls status until the call completes.
Create an agent, publish the draft, start an outbound run to a phone number, and return the transcript once the call ends
Agent Evaluation and Regression Testing
Teams shipping voice agents use Cumulus Talos to catch regressions before a new version goes live. A test suite holds cases that are run as scored trials against a specific agent version, and the results report per-case outcomes and transcripts. An agent or CI step can estimate a test run's cost, launch it, and read the pass rate before promoting the version.
Create a test suite with three cases, start a test run against the latest agent version, and return the pass rate from the case results
Telephony Provisioning
Before an agent can take calls it needs numbers and routing, which Cumulus Talos manages directly. You can import a phone number, connect a SIP trunk for carrier routing, and set an outbound call limit to cap spend. These controls sit alongside budgets and rate cards so an operator can bound both call volume and cost.
Import a phone number, connect a SIP trunk, and set the outbound call limit for the account
Key Endpoints
105 endpoints — the cumulus talos api builds, runs, and evaluates conversational voice agents that operate over the phone and the web.
METHOD
PATH
DESCRIPTION
POST
/api/v1/agents
Create an agent
POST
/api/v1/runs
Start a run
GET
/api/v1/runs/{run_id}/transcript
Get a transcript
GET
/api/v1/runs/{run_id}/recording
Get a recording URL
POST
/api/v1/telephony/numbers
Import a phone number
POST
/api/v1/test-runs
Start a test run
GET
/api/v1/voices
List speech models and voices
POST
/api/v1/agents
Create an agent
POST
/api/v1/runs
Start a run
GET
/api/v1/runs/{run_id}/transcript
Get a transcript
GET
/api/v1/runs/{run_id}/recording
Get a recording URL
POST
/api/v1/telephony/numbers
Import a phone number
POST
/api/v1/test-runs
Start a test run
GET
/api/v1/voices
List speech models and voices
Jentic AI Readiness Score
This API is usable in Jentic One now. Its AI-readiness score against Jentic's framework shows where it stands today and where improvements would make it even easier for agents to use.
C
Cumulus Talos API
- Non-Ready (F)40/100
73
Foundational Compliance69
Developer Experience & Jentic Compatibility17
AI-Readiness & Agent Experience83
Agent Usability60
Security75
AI DiscoverabilityPowered by JenticScoring Framework 1.0.0 | Scoring Engine 0.4.2
Show dimension breakdown
73
Foundational Compliance
Base layer of spec validity and structural soundness.
Grade: A-Signals: 4
92%
Lint Results
Aggregated quality score from linter diagnostics, weighted by severity.
100%
Resolution Completeness
Percentage of `$ref` references that resolve successfully.
0%
Specification Validity
Checks whether the API description parses successfully and conforms to its declared specification (e.g., OpenAPI).
100%
Structural Integrity
Structural correctness score based on schema issues using logarithmic dampening.
69
Developer Experience & Jentic Compatibility
Clarity, completeness, and ingestion readiness for developers and tooling.
Grade: B+Signals: 4
0%
Example Density
How richly the API is illustrated with examples.
100%
Example Validity
Percentage of examples that conform to their schemas.
75%
Response Coverage
Percentage of operations with complete response definitions (success, client error, server error).
100%
Tooling Readiness
Health of API ingestion, bundling, and resolution within Jentic pipelines.
17
AI-Readiness & Agent Experience
Semantic breadth, depth, and agent comprehension for AI systems.
Grade: FSignals: 4
7%
Description Coverage
Coverage of descriptions across API elements.
0%
Error Standardization
Coverage of RFC 9457 Problem Details for error responses.
0%
OperationId Quality
Coverage, uniqueness, and casing consistency of operationIds for AI inference.
59%
Summary Coverage
Coverage of summaries across operations/tags/info.
83
Agent Usability
Functional utility, complexity comfort, and AI orchestration readiness.
Grade: ASignals: 1
83%
Complexity Comfort
Agent comfort level based on API operational and structural complexity.
60
Security
Trust, risk posture, and security compliance.
Grade: B-Signals: 1
60%
Authentication Strength
Average quality of security schemes based on authentication method strength (weakest link for OAuth2).
75
AI Discoverability
Findability, semantic richness, and reasoning readiness.
Grade: A-Signals: 1
75%
Descriptive Richness
Clarity and depth of descriptions across API elements.
Score it yourself
Every API in the directory is allowlisted, so you can re-score it with no key required.
npx @jentic/api-scorecard-cli score <openapi-url>Why Jentic?
What agents get from Jentic-routed access to this vendor.
Setup
Wiring the Cumulus Talos API by hand means handling its bearer tokens, Idempotency-Key headers on writes, asynchronous run and test-run jobs, event streams, and telephony setup for numbers and SIP trunks. Through Jentic you install once, import Cumulus Talos from the API Directory, store the token once, and your agent calls it.
Permission scoping
Cumulus Talos puts the agent id and run id in the URL path, so a rule can pin your agent to one agent's runs and the transcript and analysis reads it needs. Destructive operations like phone-number release or API key rotation stay out of that set unless you add them.
Credential isolation
Your Cumulus Talos token is stored once, encrypted, by your own Jentic One instance and injected at execution time. It never enters the agent's prompt, logs, or context.
Intent-based discovery
Agents search Jentic by intent such as 'run a phone call' or 'evaluate an agent', and Jentic returns the matching Cumulus Talos operation with its input schema so the agent calls the right endpoint without browsing the reference docs.
Related APIs
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using Cumulus Talos API through Jentic.
What authentication does the Cumulus Talos API use?
The Cumulus Talos API authenticates with a bearer token per its OpenAPI spec: every request sends an Authorization header carrying your API key. Write operations also accept an Idempotency-Key header so a retry does not duplicate an agent, run, or key. Through Jentic the token is stored once, encrypted, by your own Jentic One instance and injected at call time.
Can I get call recordings and transcripts with the Cumulus Talos API?
Yes. After a run completes you can fetch a recording URL, a transcript, and a post-run analysis, and you can read or stream run events while a call is still live. Each run also reports its own usage and cost.
What are the rate limits for the Cumulus Talos API?
The OpenAPI spec does not define rate limits for the Cumulus Talos API. It does let you set per-account outbound call limits and budgets, and you can check the Cumulus Labs documentation at https://docs.cumuluslabs.io for current limits.
Is there a Cumulus Talos MCP server?
You don't need an MCP server to connect your agent to the Cumulus Talos API. Jentic imports it directly from the API Directory: store your token once and your agent can build agents, start runs, and read transcripts. Operations are discovered on demand instead of loading another server's tool definitions into context.
Can I limit what my agent is allowed to do with the Cumulus Talos API?
Yes. Write a rule that allows only the operations the task needs, such as starting runs and reading transcripts, so destructive operations like releasing phone numbers, disconnecting SIP trunks, or revoking API keys are not included unless you add them. Every call the agent makes is logged.
How do I start a voice call with the Cumulus Talos API through Jentic?
Search Jentic for 'start a voice agent run', and it returns the matching Cumulus Talos operations with their input schemas. Your agent creates and publishes an agent, starts a run against a provisioned number, and reads the transcript when the call ends. To run it on your own infrastructure, install Jentic One from its GitHub repo.
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