Agentic Index

Agentic Index

Smallest AI vs Vapi (2026)

Smallest AI and Vapi both price voice agents by the minute with free credits to start, and they differ on who makes the models. That verdict is the Agentic Index coverage score, graded from each vendor's own published materials.

Smallest AI builds its own, Lightning text to speech and Pulse speech to text, and runs them under Atoms, its no code agent builder, at 9 to 21 cents a minute depending on the models chosen, as low as 5 cents, plus a 1 cent a minute hosting fee and 10 dollars in free credits. Vapi builds none: it charges a 5 cent a minute hosting fee and passes transcriber, model and voice through at provider cost with no markup, which its calculator puts at about 82 to 129 dollars per 1,000 minutes on default providers, with 5 dollars in free credits. The grids are level on every axis but testing, where Vapi is Full and Smallest AI Partial. Choose Smallest AI for one vendor's tuned stack; choose Vapi to pick each layer.

This comparison is published by Agentic Index, an independent agentic AI vendor research platform. Smallest AI and Vapi are each graded against the same 14 capability Agentic Index taxonomy, from the vendor's own public materials under the Agentic Index verification standard, alongside 955 researched vendors. No vendor pays for placement and no vendor has reviewed this page. How this evidence is graded

Choose Smallest AI if

  • You want speech and voice models built and tuned by the same vendor as the agent builder.
  • A per minute rate that includes the models, from 5 to 21 cents, is simpler than assembling providers.
  • A no code builder should let non engineers ship agents in more than twenty languages.

Choose Vapi if

  • Choosing each provider layer yourself, with fallbacks on failure, is central to your quality plan.
  • Testing is a gate: Vapi is Full on testing and debugging where Smallest AI is Partial.
  • A HIPAA add on at a published 2,000 dollars a month lets you budget compliance up front.
Feature
S
Smallest AI
V
Vapi
Action & orchestration

Integrations & Tool Calling

Ability to connect agents to real systems through native integrations, OAuth-authenticated actions, custom tools, APIs, webhooks, or MCP-compatible tools.

Workflow Orchestration

Ability to sequence, branch, retry, route, and combine deterministic workflow nodes with autonomous agent steps.

Triggers & Channel Coverage

How agents wake up and where they work: schedules, webhooks, message events, CRM events, inbox events, chat, email, voice, and collaboration tools.
Knowledge & context

Knowledge Grounding & RAG

Ability to ground agent behavior in company data through document ingestion, retrieval, external knowledge APIs, semantic search, or RAG layers.

Memory & State Persistence

Ability to persist context across a run, conversation, workflow, user, team, or longer-term memory layer.
Control & trust

Human Oversight & Guardrails

Approval steps, consent checkpoints, escalation rules, structured guardrails, policy constraints, and pause/resume controls.

Security, Identity & Governance

RBAC, SSO, auditability, encryption, least-privilege tool access, compliance posture, and data handling policy.

Observability & Auditability

Traces, logs, execution histories, metrics, audit events, and debugging detail for production agent behavior.

Deployment & Data Residency

Deployment modes and options, including SaaS, dedicated cloud, VPC, on-prem, hybrid, local runtime, and self-hosting.
Solution readiness

Prebuilt Agents, Templates & Packs

Ready-made workflows, packaged employees, templates, blueprints, industry solutions, and role-specific agents that reduce time-to-value.
Platform extensibility

Model Flexibility & Routing

Ability to work across multiple foundation models, route tasks to different models, or let buyers bring their own providers and keys.

APIs, SDKs & MCP Extensibility

Composability layer: stable APIs, SDKs, MCP tool consumption/serving, custom tools, and integration into internal systems.

Testing, Debugging & Optimization

Testing, debugging, scoring, retries, fallbacks, quality gates, and optimization loops for improving agent workflows before and after deployment.
Specialist automation

Browser & Computer Use

Browser, desktop, or remote/local computer control for workflows that cannot be handled through stable APIs alone.

Pricing snapshot

Sourced from the Index pricing dataset · open each vendor's profile for full detail.

Pricing
S
Smallest AI
V
Vapi

Entry price

Lowest public entry point

 Pay as you go from $0.05 a minute ($0.09 to $0.21 depending on models), plus $0.01 a minute hosting. New accounts get $10 in free credits. $0.05 a minute hosting fee plus provider costs, usage based. Success packages from $29 a month.

Pricing confidence

How public the numbers are

 Public, exact Public, exact

Billing

Primary billing axis

 Per agent minute by model choice, plus a per minute hosting fee. Usage, billed per call minute and prepaid.

Variable cost

Workload / overage exposure

 High variable cost High variable cost

Free tier / trial

Try before you buy
Free tier
Free tierTrial

Buying motion

Self-serve vs sales call

 Mixed Mixed
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