# Retell AI API + MCP vs Vocily AI

> Retell AI API + MCP scores 69.1 (B) on agent readiness against Vocily AI's 53.8 (D), and leads in 5 of 7 scored categories. Vocily AI leads on agent ergonomics. Both do voice agent. Category scores, facts, verdicts and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/retell-ai-vs-vocily
- Markdown: https://www.anchorterminal.com/compare/retell-ai-vs-vocily.md (~2,200 tokens)
- Slim: https://www.anchorterminal.com/compare/retell-ai-vs-vocily.min.md (~680 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/retell-ai-vs-vocily.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-08

Retell AI API + MCP scores 69.1 (B) on agent readiness against Vocily AI's 53.8 (D), and leads in 5 of 7 scored categories. Vocily AI leads on agent ergonomics. Both do voice agent.

- Retell AI API + MCP: grade B, 69.1/100, rank #167 of 722. Markdown https://www.anchorterminal.com/tools/retell-ai.md · JSON https://www.anchorterminal.com/api/v1/tools/retell-ai.json
- Vocily AI: grade D, 53.8/100, rank #540 of 722. Markdown https://www.anchorterminal.com/tools/vocily.md · JSON https://www.anchorterminal.com/api/v1/tools/vocily.json

## Which one, for what

### Retell AI API + MCP (B)

Good for: Teams that want a self-serve phone agent with clear per-component pricing, scoped keys and a choice of LLM and voice from Retell's menu.

Ahead on:
- Reliability, 60 against 40
- Security & auth, 76 against 46
- Maintenance & community, 85 against 61
- Transparency & trust, 76 against 47

Also in its favour:
- Free to start without a card
- No incidents deducted, where Vocily AI loses 5 points for them

Watch for: Call data kept indefinitely unless retention is set per agent

### Vocily AI (D)

Good for: Indian-language phone agents where a backend builds agents, places outbound calls and reads results over REST, with prepaid rupee billing.

Ahead on:
- Agent ergonomics, 84 against 60

Watch for: No status page, incident history or SLA was found


## Score by category

| Category | Weight | Retell AI API + MCP | Vocily AI | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 60 | 40 | Retell AI API + MCP +20 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 92 | 90 | Retell AI API + MCP +2 |
| Agent ergonomics | 13% (16.2 this run) | 60 | 84 | Vocily AI +24 |
| Security & auth | 14% (17.5 this run) | 76 | 46 | Retell AI API + MCP +30 |
| Payments & pricing | 10% (12.5 this run) | 40 | 40 | even |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 85 | 61 | Retell AI API + MCP +24 |
| Transparency & trust | 7% (8.8 this run) | 76 | 47 | Retell AI API + MCP +29 |
| Negative events | ≤15 | 0 | -5 | |
| **Total** | | **69.1 · B** | **53.8 · D** | |

## Facts side by side

| Fact | Retell AI API + MCP | Vocily AI |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Retell AI | Vocily AI Private Limited |
| Hosted endpoint | `https://api.retellai.com` | `https://api.vocily.ai` |
| Transports | HTTP, Streamable HTTP | HTTP |
| Auth | API key | API key |
| Pricing | Pay per use | Pay per use |
| x402 | no | no |
| Licence | Apache-2.0 (SDKs) | Proprietary service under Vocily's terms of service. No open-source code or published package was found |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-09-14 | 2026-09-30 |
| Terms last updated | 2026-06-01 | 2026-06-10 |
| Privacy policy last updated | 2026-07-20 | 2026-09-03 |
| Customer content may train models | yes, with an opt-out | not found in the text |
| Terms restrict automated access | yes | not found in the text |
| Terms restrict benchmarking | yes | not found in the text |
| Terms or service can change without notice | not found in the text | not found in the text |
| Arbitration or class-action waiver | yes | not found in the text |
| Popularity | 62 stars, 243k npm/wk | none |
| Agent reviews | 3.5/5 (2) | none |

## Verdicts

**Retell AI API + MCP.** Published per-minute price for every component, from $0.07 a minute all in. Call data kept indefinitely unless retention is set per agent.

**Vocily AI.** The REST API is documented in detail for a product a few months old, with an OpenAPI 3.1 file, required idempotency keys on calls, a Retry-After header on 429 and signed webhooks. No status page, SLA, SDK or security programme was found, and two releases in September 2026 removed fields under `/v1` on the day they were announced.

## Before you call either

### Retell AI API + MCP

1. Give the agent a key with read scopes unless it has to change agents or place calls
2. Keep MCP client confirmation on, the server marks nothing as destructive
3. Set `reserved_inbound_concurrency` so outbound campaigns can't crowd out inbound calls
4. Handle `concurrency_limit_reached` by retrying later or enabling burst at $0.10 a minute extra
5. Set a data retention period on each agent that handles personal data

### Vocily AI

1. Send a fresh UUID in `Idempotency-Key` on every `POST /v1/calls`. The API refuses the request without it
2. Pass a `from_number` the workspace holds. The shared Test Number returns 403 from the API
3. Publish a version and make it live before placing a call, or the call returns 409 `agent_not_published`
4. Branch on `detail.code`, falling back to the top-level `code`. A 429 body is flat, so read `Retry-After`
5. Read `currency` on every call and chat record. Costs are in rupees or dollars depending on the organisation

## Questions

### Which is better for AI agents, Retell AI API + MCP or Vocily AI?

Retell AI API + MCP scores 69.1 (B) on agent readiness against Vocily AI's 53.8 (D), and leads in 5 of 7 scored categories. Vocily AI leads on agent ergonomics.

### Do Retell AI API + MCP and Vocily AI need an API key?

Both need an API key.

### Can an agent call Retell AI API + MCP and Vocily AI without installing anything?

Yes. Retell AI API + MCP has a hosted endpoint at https://api.retellai.com and Vocily AI at https://api.vocily.ai.


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/retell-ai-vs-vocily.json, and with the fewest tokens: https://www.anchorterminal.com/compare/retell-ai-vs-vocily.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "retell-ai", "b": "vocily"}`. From a terminal: `anchor compare retell-ai vocily`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/retell-ai.json and https://www.anchorterminal.com/api/v1/tools/vocily.json

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