Attentive SMS API
REST API for the Attentive SMS marketing platform enabling programmatic subscriber management, contact attribute syncing, custom event triggering, and campaign automation for retail and e-commerce brands.
Score Breakdown
⚙ Agent Friendliness
🔒 Security
All traffic over TLS. API key authentication is simple but lacks scope granularity — a single key grants full account access. No per-key permission scoping is available. Webhook events support HMAC-SHA256 signature verification. PII (phone numbers) is transmitted in request payloads and should be treated as sensitive.
⚡ Reliability
Best When
Your brand already uses Attentive for SMS marketing and you need to sync subscriber data, trigger messages from external systems, or integrate with a custom checkout or loyalty platform.
Avoid When
You need full programmatic control over campaign creation, message content, and send scheduling — the Attentive API is primarily a data sync and event trigger interface, not a full campaign management API.
Use Cases
- • Sync subscriber opt-in status and custom attributes from an e-commerce platform to Attentive when users update their profiles
- • Trigger transactional SMS messages (order confirmation, shipping update) by firing custom events via the API when fulfillment status changes
- • Add or remove subscribers from specific Attentive segments based on CRM lifecycle stage changes
- • Subscribe customers to Attentive from a custom sign-up flow outside of Attentive's native web sign-up units
- • Forward unsubscribe events from Attentive webhooks to a master suppression list in an external CRM
Not For
- • Bulk promotional SMS campaigns without prior subscriber opt-in — Attentive is a consent-based platform and does not allow sending to non-opted-in numbers
- • Voice calls or MMS-heavy multimedia messaging — Attentive focuses on SMS and basic MMS, not rich media or voice
- • Low-volume transactional SMS for non-marketing use cases — consider Twilio or Vonage for infrastructure-level messaging
Interface
Authentication
API key authentication using a Bearer token passed in the Authorization header. API keys are generated in the Attentive dashboard and are account-scoped with no granular permission scopes. A single API key grants full access to all API endpoints for the account. Key rotation must be done manually in the dashboard.
Pricing
Attentive is an enterprise SMS marketing platform. Pricing is negotiated and not publicly listed. API access is included with platform subscriptions. No self-serve or pay-as-you-go tier.
Agent Metadata
Known Gotchas
- ⚠ Phone numbers must be submitted in E.164 format (+1XXXXXXXXXX) — the API returns an error for non-standard formats but the error message may not clearly indicate the format requirement
- ⚠ Custom events must be pre-defined in the Attentive dashboard before they can be triggered via the API — agents cannot create new event types programmatically, requiring human setup coordination
- ⚠ Subscriber status (opted-in vs opted-out) can only be changed in the opted-in direction via the API; opt-outs must be processed through the unsubscribe flow and cannot be reversed programmatically
- ⚠ Webhook payloads for inbound SMS and unsubscribe events require signature verification using HMAC-SHA256 — agents must implement verification or risk processing spoofed events
- ⚠ The API does not expose campaign creation or message content management — all campaign logic must be configured in the Attentive UI, limiting agents to data sync and event trigger use cases only
Alternatives
Full Evaluation Report
Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for Attentive SMS API.
Scores are editorial opinions as of 2026-03-06.