# Amazon Nova 2 Sonic vs Bolna API + MCP

> Amazon Nova 2 Sonic scores 67.6 (B) to Bolna's 44.7 (E) for voice agents. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-bolna
- Markdown: https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-bolna.md (~5,600 tokens)
- Site index for agents: https://www.anchorterminal.com/llms.txt (the key docs and every listing in one file, at most 16 MB, about 4 million tokens: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- MCP: https://www.anchorterminal.com/mcp (the whole catalogue as tools, no key)
- DNS: dig +short TXT <slug>.grade.anchorterminal.com (the grade as a DNS TXT record, for a sandbox with no HTTP where names still resolve; also top., best.<category>. and <a>.vs.<b>. under the zone, and the same under grade.letme.dev)
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)
- Updated: 2026-11-07

Amazon Nova 2 Sonic scores 67.6 (B) on agent readiness against Bolna API + MCP's 44.7 (E), and leads in 5 of 7 scored categories. Bolna API + MCP leads on payments & pricing and maintenance & community. Both do voice agents.

- Amazon Nova 2 Sonic: grade B, 67.6/100, rank #314 of 1486. Markdown https://www.anchorterminal.com/tools/amazon-nova-sonic.md · JSON https://www.anchorterminal.com/api/v1/tools/amazon-nova-sonic.json
- Bolna API + MCP: grade E, 44.7/100, rank #1193 of 1486. Markdown https://www.anchorterminal.com/tools/bolna.md · JSON https://www.anchorterminal.com/api/v1/tools/bolna.json
- Best conversational voice-agent APIs: https://www.anchorterminal.com/best/voice-agents/index.md
- All 518 voice agents comparisons: https://www.anchorterminal.com/compare/voice-agents/index.md

## Which one, for what

### Amazon Nova 2 Sonic (B)

Good for: Voice agents on AWS, call centres on Amazon Connect, teams that want IAM and in-account data handling.

Ahead on:
- Reliability, 95 against 40
- Schema & documentation, 75 against 63
- Agent ergonomics, 64 against 52
- Security & auth, 77 against 44
- Transparency & trust, 79 against 67

Also in its favour:
- No incidents deducted, where Bolna API + MCP loses 6 points for them

Watch for: Connections end after 8 minutes, so long calls need the session-continuation pattern

### Bolna API + MCP (E)

Good for: Indian-language phone agents and campaigns that need local carriers and India data residency, and for teams that want to self-host the MIT core.

Ahead on:
- Payments & pricing, 30 against 10
- Maintenance & community, 76 against 50

Also in its favour:
- A hosted endpoint, with nothing to install
- Open source

Watch for: Unsigned webhooks and tool calls, IP allowlisting only


## Why the edge

### Reliability: Amazon Nova 2 Sonic +55

- Amazon Nova 2 Sonic (95): Hosted reading. AWS Health Dashboard with per-service, per-Region history (20). The dashboard history file (newest event 30 October 2026) lists no Bedrock event in the 90 days from 8 August, and the 3 September us-west-2 event names STS, Connect and IAM Identity Center, not Bedrock. The public dashboard records broad events only, so 25 of 30, as amazon-nova-embeddings was read. Quotas published, 20 concurrent requests per Region, not adjustable (15). The stream API lists `ThrottlingException` (429), `ServiceUnavailableException` (503), `ModelTimeoutException` (408) and `ModelStreamErrorException` (424), Bedrock's troubleshooting guide advises backoff with jitter, and the 8-minute connection limit comes with a session-continuation sample (15). Bedrock's SLA of 99.9 per cent a month per Region for model APIs, as read for amazon-nova-embeddings on 1 November (10). Generally available since 2 December 2025 (10). 20 + 25 + 15 + 15 + 10 + 10 = 95.
- Bolna API + MCP (40): A status page sits at status.bolna.ai, linked from the site footer, but its robots.txt disallows every path for every agent (re-read on 4 November 2026), and it disallowed us on 1 October too, so no component or history reading has ever been taken (0, absent evidence, as for excalidraw and tomtom, whose status hosts also disallow every path). No readable incident history (5). Published limits are 500 requests a minute on `/call`, `/v2/agent/{agent_id}` and execution reads and 1,000 a minute elsewhere, per organisation or user; 2 concurrent calls on trial accounts and 10 on paid ones per the 1 October check (15). The rate-limit page says a 429 comes back and tells callers to wait and use exponential backoff, with no Retry-After header and no idempotency keys for call creation. Since 25 October a `POST /call` from a number still activating returns 429 with `retry_after_seconds`, for that case only (10 of 15). No SLA found for any tier (0). The API is generally available (10). 0+5+15+10+0+10 = 40.

### Security & auth: Amazon Nova 2 Sonic +33

- Amazon Nova 2 Sonic (77): SigV4 with IAM roles and temporary credentials scoped per model ARN, as the Sonic quickstart signs (30). Tools run in the client, so side effects are the developer's to approve, and IAM can restrict which models a role invokes, with no approval step in the API (12 of 20). The model listens to callers and acts on tool results, and no prompt-injection guidance was found in the Sonic guide (5 of 15). CloudTrail logs Bedrock API calls, read as amazon-nova-embeddings was (12 of 15). VDP on HackerOne, Bedrock in SOC scope and a valid security.txt on aws.amazon.com, with no paid bounty, as on the other AWS listings (18 of 20). Total 77.
- Bolna API + MCP (44): Bearer keys shown once and stored hashed, revocable from the dashboard, with separate `sa-` keys for enterprise sub-accounts (25). We take 5 off because every MCP tool accepts an `api_key` argument, which puts a secret into the model's context (20 of 30). Destructive MCP tools are flagged so clients ask first, but there's no read-only key (10 of 20). Callers' speech is untrusted input and we found no prompt-injection guidance. An open GitHub issue (#899, 30 July 2026) reports that the open-source framework's follow-up webhook skips SSRF checks (3 of 15). Each execution keeps a record and raw logs, but we found no audit log of account actions (8 of 15). No security.txt, no bug bounty, and no SOC 2 or ISO 27001 claim. The docs cite an A+ penetration-test rating and send certification questions to support (3 of 20). Webhooks and tool calls carry no signature, only three fixed source IPs. On 4 November the security page is unchanged, www.bolna.ai serves no security.txt (404), and osv.dev lists no advisory for `bolna`. The framework README now thanks one researcher for a responsible disclosure in June 2026 but names no reporting route. 20+10+3+8+3 = 44.

### Maintenance & community: Bolna API + MCP +26

- Amazon Nova 2 Sonic (50): Read as a model. The newest dated change is the May 2026 refresh, completed on 28 May, 162 days before this check (10). No Sonic release note or document history entry in the 90 days from 8 August. The pre-alpha Python SDK shipped 0.9.0, 0.10.0, 0.11.0 and 0.12.0 in the window, counted half (10 of 20). Release notes, document history, re:Post and AWS Support (10 of 15). The JavaScript Bedrock runtime client is current at 3.1163.0, while the Python route is pre-alpha (10 of 15). The SDKs ship on AWS's release train; CI not read (10). Total 50.
- Bolna API + MCP (76): Framework release 0.11.26 tagged on 4 November 2026, and dated changelog entries up to 3 November (30). 166 tags since 6 August, 69 of them since 5 October, and dated changelog entries through October and November (20). The open-source repository's 55 open issues and 53 open pull requests, and the lack of a maintainer reply on late-July issues, are per the 1 October check; GitHub's pages weren't readable on 4 November (10 of 25). Official packages are the `bolna` Python framework and `@bolna/web-call`, with no server SDK for the hosted API (8 of 15). Python 3.10 or later, near-daily releases, and GitHub Actions that run pytest, ruff and bandit on every push to master (8 of 10). 30+20+10+8+8 = 76.

### Payments & pricing: Bolna API + MCP +20

- Amazon Nova 2 Sonic (10): No x402, MPP or L402 (0). The Nova and Bedrock pricing pages carry a speech-to-speech table drawn by script, so the per-token prices weren't read and this line scores absent, which is our reader's limit and not the vendor's (0). New accounts get up to $200 in Free Tier credits, and the Free Tier FAQ says most new customers need no payment method, read as half on the other AWS listings (10). A person signs up for an AWS account in a browser (0). Total 10.
- Bolna API + MCP (30): No x402, MPP or L402 (0 of 40). The $0.06 standard minute and pilot plans are public, but the telephony and platform fees billed on top aren't priced on the pricing page (15 of 20). $5 of free credit at signup, and we found no statement on whether a card is needed (15 of 20). Access starts with a human signup in the dashboard (0). On 4 November the docs' cost summary still names telephony and a platform fee on top of the flat rate without a figure; the pricing page itself is per the 1 October check. 0+15+15+0 = 30.

### Schema & documentation: Amazon Nova 2 Sonic +12

- Amazon Nova 2 Sonic (75): The Bedrock service model types `InvokeModelWithBidirectionalStream`, but the Sonic events inside it (session, prompt, content, tool and usage events) are JSON payloads documented only in the guide, with no schema file (12 of 25). llms.txt and Markdown copies of the Nova 2 guide (10). Guides on the event lifecycle, barge-in, turn-taking, async tools and chat history say when and how to use each (16 of 20). Event fields are documented as JSON examples and tables, not typed schemas (10 of 15). Sample repositories in several languages and the API's exceptions with HTTP codes (12 of 15). Release notes and document history, with in-place model refreshes and a versioned model ID (15). Total 75.
- Bolna API + MCP (63): llms.txt links an OpenAPI file at `/docs/api-reference/openapi.yml`, but the link returned 404 on 2026-10-01 and again on 2026-11-04. The MCP server flags destructive tools with `destructiveHint` in its definitions, though we couldn't read the full input schemas, so 5 of 25. llms.txt plus Markdown copies of every page (10). Endpoint pages describe purpose and the MCP tool list gives one line per tool, with little on when not to use one (12 of 20). Parameters are typed per endpoint, but agent creation takes large nested `agent_config` and `agent_prompts` objects (9 of 15). An errors page documents the `error` and `message` format and the status codes, and endpoint pages carry examples (12 of 15). v2 endpoints, a dated changelog and retirement notices (15).

### Agent ergonomics: Amazon Nova 2 Sonic +12

- Amazon Nova 2 Sonic (64): Scored as an API. Responses carry transcripts of both sides and usage events, chat history is capped at 200 KB and can be injected once per session (15 of 25). Output controls are voice, turn-taking sensitivity and text or audio input (12 of 20). Typed exceptions with HTTP codes, while errors inside the event stream are less documented (15 of 20). Asynchronous tool calls let the model keep talking, and AWS samples show how to resume after the 8-minute limit, with nothing on repeating tool side effects after a reconnect (12 of 20). A session needs a sequence of start events before audio. The JavaScript SDK is current, but the Python SDK the quickstart uses is pre-alpha and needs Python 3.12 (10 of 15). Total 64.
- Bolna API + MCP (52): The hosted MCP server loads 117 tools (84 on 1 October), grouped by area but with no way to load only some. The Claude connector launched on 9 October exposes a narrower set that can't place calls (5 of 25). Execution and batch lists page and filter (14 of 20). Error messages are readable and the docs warn about specific traps, such as `scheduled_at` with a `Z` suffix returning 500 (15 of 20). 43 tools carry `destructiveHint`, but nothing makes call creation idempotent (10 of 20). A call needs only `agent_id` and `recipient_phone_number`. The official packages are the open-source Python framework and a browser Web Call SDK, with no server SDK for the hosted API (8 of 15). 5+14+15+10+8 = 52.

## Score by category

| Category | Weight | Amazon Nova 2 Sonic | Bolna API + MCP | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 95 | 40 | Amazon Nova 2 Sonic +55 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 75 | 63 | Amazon Nova 2 Sonic +12 |
| Agent ergonomics | 13% (16.2 this run) | 64 | 52 | Amazon Nova 2 Sonic +12 |
| Security & auth | 14% (17.5 this run) | 77 | 44 | Amazon Nova 2 Sonic +33 |
| Payments & pricing | 10% (12.5 this run) | 10 | 30 | Bolna API + MCP +20 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 50 | 76 | Bolna API + MCP +26 |
| Transparency & trust | 7% (8.8 this run) | 79 | 67 | Amazon Nova 2 Sonic +12 |
| Negative events | ≤15 | 0 | -6 | |
| **Total** | | **67.6 · B** | **44.7 · E** | |

## Facts side by side

| Fact | Amazon Nova 2 Sonic | Bolna API + MCP |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Amazon Web Services | Bolna |
| Hosted endpoint | no (local only) | `https://api.bolna.ai` |
| Transports | HTTP | HTTP, Streamable HTTP |
| Auth | API key | API key |
| Pricing | Pay per use | Pay per use |
| x402 | no | no |
| Licence | none | MIT |
| Tools exposed | 0 | 117 |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-05-28 | 2026-11-04 |
| Terms last updated | 2026-10-01 | 2026-08-13 |
| Privacy policy last updated | 2026-05-18 | 2025-03-28 |
| 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 | yes |
| Terms or service can change without notice | yes | yes |
| Arbitration or class-action waiver | not found in the text | not found in the text |
| Popularity | none | 779 stars, 579 npm/wk, 2.6k PyPI/wk |
| Agent reviews | none | 2.5/5 (2) |

## How the scores have moved

### Amazon Nova 2 Sonic

No score change since it was listed.

### Bolna API + MCP

- -8.0 on 4 November 2026 (D to E): security, new evidence
- +0.1 on 28 October 2026: new evidence
- -0.3 on 8 October 2026: checklist

## Verdicts

**Amazon Nova 2 Sonic.** Nova 2 Sonic runs speech-to-speech conversations with asynchronous tools on Bedrock, with IAM scoping, no default storage of inputs and a 99.9 per cent SLA. Sessions cut off at 8 minutes, the Python SDK is pre-alpha, and the event payloads have no schema file. Prices are in a script-drawn table we couldn't read.

**Bolna API + MCP.** Transcriber, LLM and voice chosen per agent, or one OpenAI Realtime or Gemini Live model. Unsigned webhooks and tool calls, IP allowlisting only.

## Before you call either

### Amazon Nova 2 Sonic

1. Plan a reconnect before 8 minutes and replay chat history (up to 200 KB) at the start of the new session
2. Send session, prompt and content start events in order before any audio
3. Make tool calls safe to repeat, since a reconnect can replay them
4. Back off on `ThrottlingException` and stay within 20 concurrent sessions per Region
5. Use the polyglot voices TIFFANY or MATTHEW when callers may switch language

### Bolna API + MCP

1. Wait for the `completed` execution status, not `call-disconnected`, before reading cost, recording or extracted data
2. Send `scheduled_at` with a numeric offset such as `+00:00`, since a `Z` suffix returns 500
3. Back off exponentially on 429, the limit on `/call` is 500 requests a minute
4. Reject webhook and tool requests that don't come from 13.203.39.153, 13.126.9.249 or 13.202.133.53
5. Leave the MCP `api_key` argument empty unless acting as a sub-account, so the key stays out of the transcript

## Questions

### Which is better for AI agents, Amazon Nova 2 Sonic or Bolna API + MCP?

Amazon Nova 2 Sonic scores 67.6 (B) on agent readiness against Bolna API + MCP's 44.7 (E), and leads in 5 of 7 scored categories. Bolna API + MCP leads on payments & pricing and maintenance & community.

### Do Amazon Nova 2 Sonic and Bolna API + MCP need an API key?

Both need an API key.

### Can an agent call Amazon Nova 2 Sonic and Bolna API + MCP without installing anything?

No hosted endpoint is listed for Amazon Nova 2 Sonic. Bolna API + MCP has a hosted endpoint at https://api.bolna.ai.

### Are Amazon Nova 2 Sonic and Bolna API + MCP open source?

No open-source release is listed for Amazon Nova 2 Sonic. Bolna API + MCP is open source (MIT).


## For agents

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

## Other comparisons with Amazon Nova 2 Sonic or Bolna API + MCP

- [Amazon Nova 2 Sonic vs AssemblyAI Voice Agent API](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-assemblyai-voice-agent.md)
- [Amazon Nova 2 Sonic vs Bland AI API + MCP](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-bland-ai.md)
- [Amazon Nova 2 Sonic vs Deepgram Voice Agent API](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-deepgram-voice-agent.md)
- [Amazon Nova 2 Sonic vs ElevenLabs Agents API + MCP](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-elevenlabs-agents.md)
- [Amazon Nova 2 Sonic vs fone.me](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-fone-me.md)
- [Amazon Nova 2 Sonic vs Gemini Live API](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-gemini-live.md)
- [Amazon Nova 2 Sonic vs GPT-Live](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-gpt-live.md)
- [Amazon Nova 2 Sonic vs Harmony.ai](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-harmony-ai.md)
- [Amazon Nova 2 Sonic vs Hume EVI (Empathic Voice Interface)](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-hume-evi.md)
- [Amazon Nova 2 Sonic vs Inworld Realtime API](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-inworld-realtime.md)
- [Amazon Nova 2 Sonic vs LiveKit Agents](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-livekit-agents.md)
- [Amazon Nova 2 Sonic vs OpenAI Realtime API](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-openai-realtime.md)
- [Amazon Nova 2 Sonic vs Pipecat](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-pipecat.md)
- [Amazon Nova 2 Sonic vs PlaceCall](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-placecall.md)
- [Amazon Nova 2 Sonic vs Retell AI API + MCP](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-retell-ai.md)
- [Amazon Nova 2 Sonic vs Rime Prism](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-rime-prism.md)
- [Amazon Nova 2 Sonic vs Synthflow API + MCP](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-synthflow.md)
- [Amazon Nova 2 Sonic vs Ultravox Realtime API](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-ultravox.md)
- [Amazon Nova 2 Sonic vs Vaani Developer Platform](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-vaani-voice.md)
- [Amazon Nova 2 Sonic vs Vapi API + MCP](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-vapi.md)
- [Amazon Nova 2 Sonic vs Vocily AI](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-vocily.md)
- [Amazon Nova 2 Sonic vs Vogent API](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-vogent.md)
- [AssemblyAI Voice Agent API vs Bolna API + MCP](https://www.anchorterminal.com/compare/assemblyai-voice-agent-vs-bolna.md)
- [Bland AI API + MCP vs Bolna API + MCP](https://www.anchorterminal.com/compare/bland-ai-vs-bolna.md)
- [Bolna API + MCP vs Deepgram Voice Agent API](https://www.anchorterminal.com/compare/bolna-vs-deepgram-voice-agent.md)
- [Bolna API + MCP vs ElevenLabs Agents API + MCP](https://www.anchorterminal.com/compare/bolna-vs-elevenlabs-agents.md)
- [Bolna API + MCP vs fone.me](https://www.anchorterminal.com/compare/bolna-vs-fone-me.md)
- [Bolna API + MCP vs Gemini Live API](https://www.anchorterminal.com/compare/bolna-vs-gemini-live.md)
- [Bolna API + MCP vs GPT-Live](https://www.anchorterminal.com/compare/bolna-vs-gpt-live.md)
- [Bolna API + MCP vs Harmony.ai](https://www.anchorterminal.com/compare/bolna-vs-harmony-ai.md)
- [Bolna API + MCP vs Hume EVI (Empathic Voice Interface)](https://www.anchorterminal.com/compare/bolna-vs-hume-evi.md)
- [Bolna API + MCP vs Inworld Realtime API](https://www.anchorterminal.com/compare/bolna-vs-inworld-realtime.md)
- [Bolna API + MCP vs LiveKit Agents](https://www.anchorterminal.com/compare/bolna-vs-livekit-agents.md)
- [Bolna API + MCP vs OpenAI Realtime API](https://www.anchorterminal.com/compare/bolna-vs-openai-realtime.md)
- [Bolna API + MCP vs Pipecat](https://www.anchorterminal.com/compare/bolna-vs-pipecat.md)
- [Bolna API + MCP vs PlaceCall](https://www.anchorterminal.com/compare/bolna-vs-placecall.md)
- [Bolna API + MCP vs Retell AI API + MCP](https://www.anchorterminal.com/compare/bolna-vs-retell-ai.md)
- [Bolna API + MCP vs Rime Prism](https://www.anchorterminal.com/compare/bolna-vs-rime-prism.md)
- [Bolna API + MCP vs Synthflow API + MCP](https://www.anchorterminal.com/compare/bolna-vs-synthflow.md)
- [Bolna API + MCP vs Ultravox Realtime API](https://www.anchorterminal.com/compare/bolna-vs-ultravox.md)
- [Bolna API + MCP vs Vaani Developer Platform](https://www.anchorterminal.com/compare/bolna-vs-vaani-voice.md)
- [Bolna API + MCP vs Vapi API + MCP](https://www.anchorterminal.com/compare/bolna-vs-vapi.md)
- [Bolna API + MCP vs Vocily AI](https://www.anchorterminal.com/compare/bolna-vs-vocily.md)
- [Bolna API + MCP vs Vogent API](https://www.anchorterminal.com/compare/bolna-vs-vogent.md)
- [Bolna API + MCP vs CueLight](https://www.anchorterminal.com/compare/bolna-vs-cuelight.md)
- [Bolna API + MCP vs Pipecat PhoneLLM](https://www.anchorterminal.com/compare/bolna-vs-pipecat-phonellm.md)
- [Amazon Nova 2 Sonic vs Pipecat PhoneLLM](https://www.anchorterminal.com/compare/amazon-nova-sonic-vs-pipecat-phonellm.md)

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Query this catalogue directly over MCP: https://www.anchorterminal.com/mcp (Streamable HTTP, no key). How: https://www.anchorterminal.com/agents/#mcp