The autonomous software engineer

Use TextKit with Devin.SMS, phone verification, and real numbers, as capabilities.

Point Devin at the TextKit skills and long-running tasks like 'add SMS 2FA' resolve against a real sandbox it can test end to end.

1. Install the skills

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

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

textkit · textkit-verify · sms-best-practices

2. Connect the MCP server

Texts, numbers, verification, contacts, broadcasts and automations become tool calls. Add this to its MCP configuration. A client that supports sign-in needs only the URL; otherwise pass a test key:

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

Every tool and how sign-in works: MCP server docs

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 TextKit Verify
(POST /v1/verify, then /v1/verify/check). Docs:
https://jointextkit.com/docs/verify.md

Everything Devin 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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