# Hail

**Canonical:** https://apis.io/providers/hail-so/  
**Website:** https://hail.so/  
**APIs profiled:** 1

Hail provides a unified API that gives AI agents a phone number and email inbox, enabling them to make and receive calls, send and receive SMS, and manage email. The platform offers easy integration for developers building AI assistants, with features like call routing, message handling, and customizable agent behavior. It targets developers seeking to add communication capabilities to AI applications, offering a simple RESTful interface and comprehensive documentation.

## Kin Score — 43.7 / 100 (developing)

Scored 2026-11-13 under rubric 0.28.0.

| Facet | Score |
|---|---|
| Discoverability | 66.1 |
| Contract Quality | 66.2 |
| Contract Governance | 35.6 |
| Operational Transparency | 14.3 |
| Developer Ergonomics | 39.9 |
| Access Clarity | 36.2 |

Regulatory layer — **Telecommunications**: 14.8 (matched via tags).

## Agent readiness — 52.2 (agent-native)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | no |
| MCP Server | no |
| Auth Clarity | served |
| Idempotency | verified |
| Error Semantics | verified |
| OpenAPI Examples | no |
| Rate Limit Signal | verified |
| Event Surface Described | yes |
| Agent Skills | derived |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | no |
| Delegated Identity | served |
| Protected Resource Metadata | no |
| Dynamic Client Registration | yes |
| Agentic Commerce | no |
| Pagination Ratio | partial |
| Operation Distinctiveness | mostly |
| MCP Tool Quality | na |

## Access

Unknown — onboarding: unknown, pricing: unknown, trial: no (confidence: low).

## APIs (17)

- **Hail Agents API** — The agents API from Hail — 2 operation(s) for agents.
- **Hail Calls API** — The calls API from Hail — 3 operation(s) for calls.
- **Hail Contacts API** — The contacts API from Hail — 3 operation(s) for contacts.
- **Hail Email Attachments API** — The email-attachments API from Hail — 1 operation(s) for email-attachments.
- **Hail Email Domains API** — The email-domains API from Hail — 5 operation(s) for email-domains.
- **Hail Emails API** — The emails API from Hail — 8 operation(s) for emails.
- **Hail Events API** — The events API from Hail — 1 operation(s) for events.
- **Hail Forward Targets API** — The forward-targets API from Hail — 2 operation(s) for forward-targets.
- **Hail Healthz API** — The Healthz API from Hail — 1 operation(s) for healthz.
- **Hail Numbers API** — The numbers API from Hail — 6 operation(s) for numbers.
- **Hail Providers API** — The providers API from Hail — 5 operation(s) for providers.
- **Hail Sms API** — The sms API from Hail — 5 operation(s) for sms.
- **Hail Unsubscribe API** — The unsubscribe API from Hail — 1 operation(s) for unsubscribe.
- **Hail Uploads API** — The uploads API from Hail — 2 operation(s) for uploads.
- **Hail Verifications API** — The verifications API from Hail — 9 operation(s) for verifications.
- **Hail Webhooks API** — The webhooks API from Hail — 6 operation(s) for webhooks.
- **Hail Whoami API** — The whoami API from Hail — 1 operation(s) for whoami.

## Agentic access (1)

- **Hail Agentic Access** — 85 operations · 43 acting

## Security (1)

- **Hail Domain Security** — TLSv1.3 · HSTS · DMARC

## Tags

Artificial Intelligence, Communications, Phone, SMS, Email

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/hail-so/). Scores are computed from the provider's own public artifacts under a published rubric.