OpenAI's coding agent

Use SimpleSMS with Codex.SMS, phone verification, and real numbers, as capabilities.

Codex reads SKILL.md files; give it SimpleSMS's and it stops hand-rolling OTP over raw SMS and uses the verify primitive instead.

1. Install the skills

Three SKILL.md files teach Codex the API, the verification rules, and SMS compliance, so it writes correct integration code the first time:

curl -sSL https://joinsimplesms.com/skills/install.sh | sh

simplesms · simplesms-verify · sms-best-practices

2. Connect the MCP server

SimpleSMS speaks Model Context Protocol. Add this to Codex's MCP configuration and messages, verification, numbers, and lookup become tool calls:

{
  "mcpServers": {
    "simplesms": {
      "url": "https://mcp.joinsimplesms.com",
      "headers": { "Authorization": "Bearer ssms_sk_test_YOUR_KEY" }
    }
  }
}

Discovery: /.well-known/mcp.json

3. Ask for the feature

A prompt like this now resolves against the real API, with a sandbox key that simulates everything and costs nothing:

Add phone verification to signup using SimpleSMS Verify
(POST /v1/verify, then /v1/verify/check). Docs:
https://joinsimplesms.com/docs/verify.md

Everything Codex needs is machine-readable: an OpenAPI spec, markdown twins of every docs page, and a single-file llms.txt of the whole documentation set.

/llms.txt
/api/v1/openapi.yaml
/docs/llms-full.txt

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