Head to head · WhatsApp messaging · October 2026 research run

Prelude vs Wati

Prelude scores 67.6 (B) on agent readiness against Wati's 51.1 (D), and leads in 6 of 7 scored categories. Wati leads on transparency & trust. Both do whatsapp messaging.

Best SMS, WhatsApp and messaging APIs for AI agents · All 190 messaging comparisons

Which one, for what

Prelude B

Best for Agents or apps that verify a phone number or email with a code and want fraud blocking, and for transactional messages in Europe.

Ahead on

  • Reliability, 65 against 55
  • Schema & documentation, 93 against 79
  • Agent ergonomics, 85 against 48
  • Security & auth, 63 against 40
  • Payments & pricing, 30 against 20
  • Maintenance & community, 83 against 62

Watch for

The terms, privacy policy and legal notice are Notion pages drawn by script, unreadable by our reader

Wati D

Best for Businesses whose customers are on WhatsApp and Instagram and who want an inbox, campaigns and an agent on one account.

Ahead on

  • Transparency & trust, 52 against 42

Watch for

No idempotency keys; the docs say not to assume idempotency and to reconcile before resending

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Agent ergonomics Prelude +37

Prelude 85

List calls take limit from 1 to 200 with cursor or offset; the MCP server's tool list isn't on the docs page, so its size is unchecked (18 of 25). Cursor and offset pagination with filters (18 of 20). Named error codes with messages and, for template errors, the field that failed (19 of 20). Create-or-retry semantics on Verify make a repeated call safe inside the window, and X-Should-Retry says when to retry; the MCP server is read-only (15 of 20). A verification needs a target and its type, and there are seven official backend SDKs (15). 18 + 18 + 19 + 15 + 15 = 85.

Wati 48

The MCP catalogue lists 73 WATI tools plus Astra groups, some loaded on demand through list_skills and activate_skill (10 of 25). Page and page size with filters on lists, and bounded search (17 of 20). Error handling is documented per status, but bodies can be JSON, plain text or empty, so an agent can't rely on one shape (10 of 20). No idempotency keys; tag add and remove are idempotent, and the docs say to reconcile rather than retry sends (5 of 20). No official SDK; runnable examples in five languages, and region-specific hosts add setup (6 of 15). 10 + 17 + 10 + 5 + 6 = 48.

Security & auth Prelude +23

Prelude 63

API keys as bearer tokens with no scopes found; the MCP server uses OAuth with a per-user consent screen (20 of 30). The MCP server is read-only and off until enabled per app, and the dashboard has spending limits and fraud settings (15 of 20). Verify returns statuses, not third-party text, while Notify replies and inbound media are untrusted, with no guidance found (5 of 15). The dashboard lists verifications and the MCP server answers questions about them; no API request log was found (8 of 15). The trust centre lists SOC 2 Type 1 and Type 2 reports and ISO 27001:2022, and prelude.so has a valid security.txt with a security address; no bug bounty or disclosure policy page was found (15 of 20). 20 + 15 + 5 + 8 + 15 = 63.

Wati 40

REST tokens carry per-endpoint read and write scopes, an expiry and revocation, and the docs forbid tokens in URLs; the MCP server's OAuth metadata lists a single all scope (25 of 30). Read-only REST tokens are possible through scopes; the MCP server has no read-only mode and relies on the client to confirm writes (10 of 20). Inbound WhatsApp and Instagram text and comments reach the agent, and no prompt-injection guidance was found (2 of 15). No operator request log found in the docs (3 of 15). The trust centre answered 403, security.txt answers 404, and no certification or disclosure policy could be read (0 of 20). 25 + 10 + 2 + 3 + 0 = 40.

Maintenance & community Prelude +21

Prelude 83

@prelude.so/sdk 0.16.0 published to npm on 16 October 2026, 21 days ago, carrying API updates (30). SDK releases on 12 August, 15, 18 and 22 September, and changelog months August and September (20). Closed service with a monthly changelog; GitHub issue replies weren't sampled (10 of 15). Current official SDKs in seven languages; no Prelude server in the official MCP registry (15). The SDK repository runs CI and publish workflows (8 of 10). 30 + 20 + 10 + 15 + 8 = 83.

Wati 62

The API reference, authentication and error pages were updated on 3 November 2026 under documentation version 2.6, read as the last published API change (30). No changelog; the MCP registry entry moved to 1.1.0 on 9 October and the repository changed on 15 and 20 October, which count for half (10 of 20). Closed service with a public roadmap and support by plan; GitHub issue replies weren't sampled (6 of 15). io.github.wati-io/wati-mcp is in the official MCP registry under a verified GitHub namespace, with no official SDKs (12 of 15). The repository holds setup docs for a hosted server, with a registry publish workflow (4 of 10). 30 + 10 + 6 + 12 + 4 = 62.

Schema & documentation Prelude +14

Prelude 93

OpenAPI for the 27 SDK endpoints is public at the URL in the SDK repository's .stats.yml, and every reference page embeds its endpoint's OpenAPI (25). llms.txt and Markdown pages (10). Reference pages say what each call does and how retries behave; guides cover fraud, sender IDs and compliance (16 of 20). Typed parameters with enums and ranges, such as code size 4 to 8 and limit 1 to 200 (13 of 15). Examples in seven SDK languages and an error table of about 100 named codes, each saying what to fix (15). Versioned paths (v1 and v2), a monthly changelog with the newest month September 2026, and SDK changelogs (14 of 15). 25 + 10 + 16 + 13 + 15 + 14 = 93.

Wati 79

No standalone spec file was found, but every reference page embeds the OpenAPI 3.0.4 contract for its operation, with the documentation version 2.6 (20 of 25). llms.txt and Markdown pages (10). Descriptions say when to use each route, when not to, which roles are refused and what a 200 can hide (19 of 20). Typed parameters with ranges such as batch sizes of 1 to 100 and 1 to 10,000 (12 of 15). Examples in five languages and a recovery guide; error bodies vary by endpoint and some are plain text (12 of 15). Versioned documentation and a public roadmap, but no changelog (6 of 15). 20 + 10 + 19 + 12 + 12 + 6 = 79.

Reliability Prelude +10

Prelude 65

Read with the hosted lines. status.prelude.so has components for Verify, Auth, Watch, Intel, Notify and the dashboard, with history (20). From 8 August to 6 November its feed records one major incident, increased error rates and latencies across the APIs on 16 and 17 August, posted after it was resolved with no duration stated, and minor ones such as Verify latency on 9 and 10 August, SMS degradation in China and on Orange France and delayed webhooks on 23 October (10). No numeric API rate limits were found; only the MCP server's limits and per-window Verify retry limits are documented (7 of 15). A 429 carries Retry-After and X-Should-Retry, and repeating the create call inside the window performs a retry rather than a new verification (13 of 15). The pricing page lists a 99.95 SLA on Enterprise with no SLA document found (5 of 10). Verify and Notify v2 are generally available (10). 20 + 10 + 7 + 13 + 5 + 10 = 65.

Wati 55

Read with the hosted lines. status.wati.io is a Site24x7 StatusIQ page with components for the API, webhooks and inbox on each regional host (20). Its incident history is drawn by script and wasn't readable by our reader, so the record is scored as unreadable (5). Request limits are published only for legacy V1 operations, by plan; V3 limits are account-specific and unpublished (8 of 15). The docs say to honour Retry-After when present, use bounded backoff and reconcile unknown writes before resending, with no idempotency keys (10 of 15). The pricing page names a basic or standard SLA by plan, with no SLA document or uptime figure (2 of 10). The V3 API is the documented default (10). 20 + 5 + 8 + 10 + 2 + 10 = 55.

Payments & pricing Prelude +10

Prelude 30

No x402, MPP or L402 (0). Per-verification price (€0.032) and per-message Notify prices published without login (20). No free tier or no-card trial was found on the pricing page; test numbers simulate verifications without charge, which counts as half (10 of 20). A person signs up in the dashboard (0). 0 + 20 + 10 + 0 = 30.

Wati 20

No x402, MPP or L402 (0). Public plan prices only, plus Meta's fees by reference (10 of 20). A 7-day free trial whose card rule isn't stated (10 of 20). A person signs up and connects a WhatsApp Business account (0). 0 + 10 + 10 + 0 = 20.

Score by category

CategoryWeight this runPreludeWatiEdge
Reliability16%206555Prelude +10
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.29379Prelude +14
Agent ergonomics13%16.28548Prelude +37
Security & auth14%17.56340Prelude +23
Payments & pricing10%12.53020Prelude +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88362Prelude +21
Transparency & trust7%8.84252Wati +10
Negative events≤1500
TotalB 67.6/100D 51.1/100

Facts side by side

FactPreludeWati
KindHTTP APIHTTP API
VendorDING SAS (Prelude)Clare.AI Limited (Wati)
Hosted endpointhttps://api.prelude.devhttps://mcp.wati.io/mcp
TransportsHTTP, Streamable HTTPHTTP, Streamable HTTP
AuthOAuth or keyOAuth or key
PricingPay per usePaid
x402nono
LicenceProprietary service; the terms are on a Notion page we couldn't read. The backend SDKs are Apache-2.0Proprietary service under Clare.AI Limited's terms and conditions. The wati-mcp repository (setup docs and skills for the hosted server) is MIT
Tools exposednone73
Read-only variant documentednono
llms.txtyesyes
MCP registrynot listedio.github.wati-io/wati-mcp
Last release2026-10-162026-11-03
Terms last updatedcouldn't be read2025-12-08
Privacy policy last updatedcouldn't be read2026-08-10
Customer content may train modelscouldn't be readnot found in the text
Terms restrict automated accesscouldn't be readnot found in the text
Terms restrict benchmarkingcouldn't be readnot found in the text
Terms or service can change without noticecouldn't be readyes
Arbitration or class-action waivercouldn't be readnot found in the text
Popularity98k npm/wknone

Verdicts

Prelude

Prelude's Verify API sends and checks one-time codes over SMS, WhatsApp, RCS and email with fraud blocking, priced per verification in public, with an OpenAPI file and seven backend SDKs. Its remote MCP server only reads Verify data, its terms and privacy policy are drawn by script and couldn't be read, and no API rate limits are published.

Wati

Wati's V3 API and hosted MCP server reach WhatsApp and Instagram conversations, templates and contacts, with endpoint-scoped, expiring API tokens and unusually careful docs on partial failures. Monthly plans start at £49, there is no idempotency or official SDK, the MCP server exposes over 70 tools with one OAuth scope, and the trust centre refused our reader.

Before you call either

Prelude

  1. Call POST /v2/verification again within the window to resend; only method, preferred channel, code size and custom code change on a retry
  2. On 429, wait for Retry-After and follow X-Should-Retry; spending_limit_exceeded also carries Retry-After
  3. Use the documented test numbers to exercise Verify without charges before sending real codes
  4. Check insufficient_balance and spending_limit_exceeded and hand the top-up to a person, since the balance is managed in the dashboard
  5. Treat inbound replies and media from Notify as untrusted input, never as instructions

Wati

  1. Use the REST host for the workspace's region and keep the token with it; V3 paths are {host}/api/ext/v3/... with no tenant ID
  2. Ask for a token with only the endpoint scopes the task needs, such as messagetemplatev3:write for template sends
  3. Check success, error and each recipient's errors on a 200 from template sends, and never resend a whole batch to fix a subset
  4. Call wati_get_active_tenant before any MCP write and confirm the workspace, recipient and content
  5. Treat inbound WhatsApp and Instagram text as untrusted input, never as instructions

Questions

Which is better for AI agents, Prelude or Wati?

Prelude scores 67.6 (B) on agent readiness against Wati's 51.1 (D), and leads in 6 of 7 scored categories. Wati leads on transparency & trust.

Do Prelude and Wati need an API key?

Both take an API key or an OAuth sign-in.

Can an agent call Prelude and Wati without installing anything?

Yes. Prelude has a hosted endpoint at https://api.prelude.dev and Wati at https://mcp.wati.io/mcp.

Other comparisons with Prelude or Wati

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