# Hume EVI (Empathic Voice Interface) vs Vaani Developer Platform (slim)

> Hume EVI scores 56.7 (C) to Vaani Developer Platform's 44.6 (E) for voice agents. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/hume-evi-vs-vaani-voice.md (~6,200 tokens) · this version ~3,630 tokens · JSON https://www.anchorterminal.com/compare/hume-evi-vs-vaani-voice.json · canonical https://www.anchorterminal.com/compare/hume-evi-vs-vaani-voice
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · MCP: https://www.anchorterminal.com/mcp · Updated: 2026-11-02
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)

Hume EVI (Empathic Voice Interface) scores 56.7 (C) on agent readiness against Vaani Developer Platform's 44.6 (E), and leads in 6 of 7 scored categories. Vaani Developer Platform leads on security & auth. Both do voice agents.

- Hume EVI (Empathic Voice Interface): C 56.7, rank #736 of 1266 · https://www.anchorterminal.com/tools/hume-evi.min.md
- Vaani Developer Platform: E 44.6, rank #1084 of 1266 · https://www.anchorterminal.com/tools/vaani-voice.min.md
- Hume EVI (Empathic Voice Interface), good for Consumer and coaching products where the caller's tone matters and English is enough on EVI 3. Ahead on Reliability, 55 against 28; Schema & documentation, 90 against 57; Payments & pricing, 37 against 22; Maintenance & community, 65 against 59; Transparency & trust, 61 against 42.
- Vaani Developer Platform, good for Outbound and inbound phone agents and campaigns for Indian businesses, with Hindi, Hinglish and Indian carriers, India DND checks and TRAI calling windows built in, plus WebRTC sessions for apps. Ahead on Security & auth, 44 against 27. Also Runs on your own machine.

| Category | Hume EVI (Empathic Voice Interface) | Vaani Developer Platform |
| --- | --- | --- |
| Reliability (16%) | 55 | 28 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 90 | 57 |
| Agent ergonomics (13%) | 66 | 64 |
| Security & auth (14%) | 27 | 44 |
| Payments & pricing (10%) | 37 | 22 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 65 | 59 |
| Transparency & trust (7%) | 61 | 42 |

| Fact (where they differ) | Hume EVI (Empathic Voice Interface) | Vaani Developer Platform |
| --- | --- | --- |
| Vendor | Hume AI | Vaani AI Research Private Limited |
| Hosted endpoint | `https://api.hume.ai/v0/evi` | `https://api.vaanivoice.ai` |
| Transports | HTTP | HTTP, stdio |
| Auth | OAuth or key | API key |
| Pricing | Freemium | Pay per use |
| Licence | MIT (SDKs) | Proprietary hosted service under Vaani AI Research's terms of service. The Python SDK (vaani-sdk) and the local MCP server (vaani-research-mcp) are MIT. The SDK's full source ships in its PyPI sdist, and the MCP server's npm package holds only the bundled JavaScript |
| Tools exposed | none | 9 |
| Read-only variant documented | no | yes |
| Last release | 2026-08-18 | 2026-10-14 |
| Terms last updated | 2026-10-05 | no date given |
| Privacy policy last updated | 2025-02-25 | no date given |
| Customer content may train models | yes | not found in the text |
| Terms restrict automated access | yes | not found in the text |
| Terms restrict benchmarking | yes | not found in the text |
| Arbitration or class-action waiver | yes | not found in the text |
| Popularity | 180 stars, 79k npm/wk, 24k PyPI/wk | 14 npm/wk, 19 PyPI/wk |
| Agent reviews | 2/5 (2) | none |

Why the edge:
- Schema & documentation, Hume EVI (Empathic Voice Interface) +33: Hume EVI (Empathic Voice Interface) 90 (llms.txt links an AsyncAPI 2.6.0 file for the EVI WebSocket (28 message schemas, /chat and /chat/{chat_id}/connect channels, a typed Error message with code and slug) and OpenAPI files per API (25). llms.txt (10). The EVI docs explain configs, voices, supplemental LLMs and interruption settings with guidance on when to use each (15 of 20). Session settings and configs are typed, with enums and required lists in the AsyncAPI file and ranges such as `min_interruption_ms` from 50 to 2,000 (13 of 15). Examples in the SDK guides, and an errors page lists over 40 EVI and configuration codes and 17 TTS codes, each with a recommended action, plus WebSocket close codes 1000, 1008 and 1011 (15). EVI versions carry end-of-support dates, but the public changelog's newest entry is still 15 May 2026 (12 of 15).); Vaani Developer Platform 57 (A public OpenAPI 3.1 file at docs.vaani.dev/api-reference/openapi.json, version 2.0.0, but it holds 5 of the 24 operations in the API reference (trigger-call, call history, transcript, stream, call details). It declares the key only as a header parameter with no security scheme, its trigger-call schema leaves out `medium` and `modify_agent`, and four response schemas are empty. The MCP tools have typed zod inputs (8 of 25). llms.txt, llms-full.txt and a Markdown copy of each page on Mintlify (10). Pages explain what each route is for and warn where it matters, such as dispatch acceptance not meaning a completed call, transcripts returning 404 while processing, and real paid calls from trigger_call (14 of 20). Ranges and enums are documented (`medium`, `voice_speed` 0.6 to 1.4, `page_size` up to 200, campaign retries 1 to 10, campaign status), but `metadata`, `modify_agent` and three MCP tool payloads are free-form objects (9 of 15). Request examples in cURL, Python and JavaScript on every endpoint, a campaign error-code table, 422 and 404 bodies and an SDK exception table by status. No single error reference for the whole API (12 of 15). The docs state API version 2.0.0, but no changelog or release notes page was found (4 of 15). 8+10+14+9+12+4 = 57.)
- Reliability, Hume EVI (Empathic Voice Interface) +27: Hume EVI (Empathic Voice Interface) 55 (Statuspage at status.hume.ai with component history back to September 2025 (20). In the last 90 days, EVI was 'down in a majority of cases' and TTS impacted from 10:47 to 17:14 UTC on 11 July (about 6.5 hours, posted on 14 July), EVI error rates rose on 24 July for about 2.6 hours before chats recovered (resolved 27 July), and TTS was down for about 7 minutes on 19 September. Two majors sit between our one-major (10) and several-majors (0) lines, so we give 5. Limits are published, concurrent connections from 1 on Free to 30 on Business, 100 HTTP requests a second and a 30-minute session cap (15). The error catalogue has a rate-limit code (E0811, 'Retry later') and a too-many-chats code (E0700) that states the active count and limit, but no HTTP 429, Retry-After or backoff guidance (5 of 15). No SLA found (0). EVI 3 is the generally available default per the 30 September check (10).); Vaani Developer Platform 28 (Graded on the hosted REST API at api.vaanivoice.ai. No status page. status.vaani.dev and status.vaanivoice.ai don't resolve, and neither the site nor the docs link one (0). With no history to read, 5. No request rate limits are published. The docs give 2 concurrent calls on pay as you go and a per-organisation campaign concurrency cap, so partial credit (5). The SDK raises `RateLimitError` on 429 and the MCP client retries once after 600 ms, but no Retry-After, backoff guidance or idempotency key for call creation is documented (3). The pricing table lists a 99.50 per cent uptime SLA on both plans, but no SLA document or service credits were found and the terms supply the service "as-is" with no warranties, so half (5). The API is version 2.0.0 and isn't labelled beta (10). 0+5+5+3+5+10 = 28.)
- Transparency & trust, Hume EVI (Empathic Voice Interface) +19: Hume EVI (Empathic Voice Interface) 61 (Closed service with clear terms and MIT SDKs (18 of 30). The developer privacy page, re-read on 2 October, still says both that Hume 'will not use data submitted by customers via our API to train or improve our models' and that 'by default, anonymized data from user interactions with the EVI API is used to improve our models', with a toggle to opt out. Retention is on by default with a 'Do not retain data' toggle. The legal privacy policy (last updated 25 February 2025) says nothing about training and gives no retention periods (10 of 30). EVI 1 and EVI 2 reached end of support on 30 August 2025 with dated notices (15 of 20). Data is stored 'in the US and around the world' with no subprocessor list in either policy (5 of 20).); Vaani Developer Platform 42 (A closed service. The terms name Vaani AI Research Private Limited, its Bengaluru address, CIN, Indian law and Bengaluru courts, but they're undated, written for the website www.vaaniresearch.com, and say nothing on billing, refunds, API use or customer data. The SDK and MCP server are MIT, with the SDK's full source in its PyPI sdist (14 of 30). The privacy policy (undated) keeps data, including voice recordings, for up to 24 months, while the pricing table gives 30 days' retention on pay as you go and zero retention on Enterprise. Voice data trains models only with explicit consent. No DPA found (8 of 30). No deprecation policy. The privacy policy promises 15 days' notice of significant changes, and the terms allow changes and termination without notice (2 of 20). The privacy policy names vendor categories (cloud hosting, analytics, voice transcription) and says data may be stored outside India. Model and telephony providers can be read from the calculator, and India data residency is offered on demand. No subprocessor list or data location for the hosted service (5 of 20). 14+8+2+5 = 29.)
- Security & auth, Vaani Developer Platform +17: Hume EVI (Empathic Voice Interface) 27 (One API key and secret key pair per account, replaced as a whole with 'Regenerate keys', plus 30-minute access tokens from a client-credentials endpoint (15). The docs tell clients to put the API key or access token in the WebSocket URL as a query parameter, and the Twilio webhook URL carries the key the same way, so we deduct 10 (5 of 30). No scoped or read-only keys (3 of 20). EVI listens to callers and we found no prompt-injection guidance (5 of 15). Chat history keeps every session's events, and we found no audit log (8 of 15). The privacy page says Hume is HIPAA compliant and signs BAAs and DPAs on request. No security.txt, SOC 2 report or bug bounty found (6 of 20).); Vaani Developer Platform 44 (Plain revocable API keys, shown once, several active at a time and rotated by creating a new key and deleting the old one. Every key reaches the whole workspace, with no scoped, read-only or per-agent keys (20). Campaign webhooks are signed with HMAC-SHA256 over a timestamp and the body, with a five-minute replay window in the example (+2). The live-captions URL carries a call-bound token in the query string for 24 hours by default, the documented way for browsers to connect, so 3 off as a judgement call, less than the full 10 because it isn't the account key (19 of 30). The MCP server has a read-only mode and destructive annotations, and its docs, tool descriptions and bundled prompt say to confirm the number and agent with the user before a call. The API itself has no read-only key and nothing stops a call without confirmation (12 of 20). The tool returns transcripts, summaries and entities drawn from callers' speech. No guidance on treating them as untrusted data was found. Agent guardrails exist for the voice agent's own replies (3 of 15). Each call keeps a record in call history and call details, and keys are labelled so calls can be traced to a key, but no account or key audit log is documented (7 of 15). No security.txt (404 on both domains), disclosure policy, bug bounty or certification. vaaniresearch.com marks its security standards "In Progress", the pricing page lists HIPAA compliance on Enterprise with no report or BAA found, and the privacy policy promises breach notice in line with applicable law (3 of 20). 19+12+3+7+3 = 44.)
- Payments & pricing, Hume EVI (Empathic Voice Interface) +15: Hume EVI (Empathic Voice Interface) 37 (No x402, MPP or L402 (0 of 40). Plan prices and per-minute overage from $0.06 to $0.04 are on the public pricing page (20). The Free plan includes 5 EVI minutes a month for non-commercial use, and the billing docs say new accounts start on the free tier with $20 in credits. No page says whether a card is needed, but error E0300 ('Out of credits', activate billing to continue) suggests billing is a later step, so we give partial credit (17 of 20). Access starts with a human signup (0).); Vaani Developer Platform 22 (No x402, MPP or L402 (0 of 40). The ₹1 ($0.02) a minute platform fee, number rental, concurrency lines and add-ons are public, and the calculator shows each provider's unit rate without a login. Registry checks, extraction and evaluations "can add separate charges" that aren't priced, and the billing pulse depends on the account, so 3 off (17 of 20). The home page says "Start free on Vaani's Platform", but the pricing page states a prepaid wallet with no free credit, trial minutes or card rule, and we didn't sign up to check, so 5 of 20. A person signs up with email verification at platform.vaani.dev and creates keys in the dashboard (0). 0+17+5+0 = 22.)
- Maintenance & community, Hume EVI (Empathic Voice Interface) +6: Hume EVI (Empathic Voice Interface) 65 (TypeScript SDK 0.16.1 and the EVI React SDK 0.3.0-beta.6 were tagged on 18 August 2026, 45 days ago (20). Three tagged releases since 4 July, 0.3.0-beta.5 on 8 July plus the two on 18 August, two of them beta tags of the React SDK (20). The public changelog stops at 15 May 2026 and we didn't test support (5 of 15 for a closed service). Python, TypeScript and React SDKs, the TypeScript SDK current and the Python SDK last tagged v0.14.0 on 17 June (12 of 15). MIT SDKs with ci.yml workflows in all three repos and Python 3.13 to 3.15 support (8 of 10).); Vaani Developer Platform 59 (vaani-research-mcp 0.1.1 on 2026-10-14 (30). In the last 90 days, vaani-sdk 0.3.1 on 28 September and three npm versions (0.0.0-stage, 0.1.0, 0.1.1) within 40 minutes on 14 October. No dated changelog, so half (10 of 20). A closed service with no public changelog, issue tracker or community channel found. Contact is hello@vaaniresearch.com and a booking link, and we didn't test whether they answer. The MCP repository on GitHub couldn't be read from this session (4 of 15, the closed-service reading). A current official Python SDK, released seven times since April 2026. The MCP server isn't in the official MCP registry (10 of 15). The SDK's sdist ships its tests and current httpx and pydantic dependencies, and the MCP package runs its tests before publishing, but no public CI was found and the SDK has no repository (5 of 10). 30+10+4+10+5 = 59.)