Install Jentic One Beta
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Buttondown API, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.
Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fbuttondown.com%2Fbuttondown" | shStep 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fbuttondown.com%2Fbuttondown" | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
What an agent can do with Buttondown API.
Add new subscribers and update their metadata
Remove subscribers from a newsletter list
Draft, schedule, and send newsletter emails
Update existing email drafts before sending
Organise subscribers and emails with tags
GET STARTED
Look up an individual subscriber by ID or email
Patterns agents use Buttondown API for, with concrete tasks.
★ Subscriber Sync from External Forms
Push new subscribers into Buttondown from external signup forms, landing pages, or CRM systems. Indie writers and small teams use this to keep Buttondown in sync without manual exports. A typical sync runs in seconds per subscriber via POST /subscribers.
Read new signups from a Google Sheet and POST each row to /subscribers with email and tag fields
Automated Newsletter Drafting
Generate newsletter drafts from external content sources - blog posts, RSS feeds, or AI summaries - and create them in Buttondown via POST /emails. Editors review the draft in the Buttondown UI before scheduling. Reduces drafting time from 30 minutes to a few seconds per issue.
Summarise the latest five blog posts, format them into a Markdown newsletter, and POST to /emails as a draft
Tag-Based Audience Segmentation
Use the /tags endpoint to create and manage tags applied to subscribers and emails. Operators use this to segment audiences for targeted sends or to track campaign performance over time. Tags can be created and listed in a single agent run.
Create a tag named 'paid-tier', list all subscribers, and apply the tag to those flagged as paid in the source CRM
AI Agent Newsletter Operations
Through Jentic, an AI agent can drive Buttondown end-to-end - adding subscribers, drafting emails, and managing tags - using natural language intent. Agents discover the right operation by searching, load the schema, and execute without scraping the docs.
Search Jentic for 'send a buttondown newsletter', load the schema for POST /emails, and execute with subject, body, and recipient list
15 endpoints — jentic publishes the only available openapi specification for buttondown api, keeping it validated and agent-ready.
METHOD
PATH
DESCRIPTION
/subscribers
Create a new subscriber
/subscribers/{idOrEmail}
Look up a subscriber by ID or email
/subscribers/{idOrEmail}
Update a subscriber
/emails
Create a newsletter email
/emails
List emails
/emails/{id}
Update an email draft
/tags
Create a tag
/subscribers
Create a new subscriber
/subscribers/{idOrEmail}
Look up a subscriber by ID or email
/subscribers/{idOrEmail}
Update a subscriber
/emails
Create a newsletter email
/emails
List emails
/emails/{id}
Update an email draft
/tags
Create a tag
What agents get from Jentic-routed access to this vendor.
Setup
Wiring Buttondown by hand means learning its token scheme, remembering the odd 'Token YOUR_API_KEY' prefix the Authorization header expects, and writing your own backoff for the undocumented 429s. Through Jentic you install once, import the Buttondown API from the API Directory, store the token once, and your agent calls it.
Permission scoping
Buttondown puts the subscriber or email id in the URL path (/subscribers/{idOrEmail}, /emails/{id}), so you can pin your agent to specific records rather than the whole audience. You choose the operations it may call, so destructive ones like deleting a subscriber or removing an email draft are not included unless you add them.
Credential isolation
Your Buttondown token is stored once, encrypted, by your own Jentic One instance and injected at execution time. It never enters the agent's prompt, logs, or context.
Intent-based discovery
Agents search Jentic by intent such as 'add a buttondown subscriber' or 'send a buttondown newsletter', and Jentic returns the matching operation with its input schema so the agent calls the right endpoint without browsing the reference docs.
Alternatives and complements available in the Jentic catalogue.
Specific to using Buttondown API through Jentic.
Why is there no official OpenAPI spec for Buttondown API?
Buttondown does not publish an OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call Buttondown API via structured tooling. It is validated against the live API and kept up to date. Get started with Jentic One, the self-hosted execution layer.
What authentication does the Buttondown API use?
Buttondown uses a token-based API key passed in the Authorization header in the format 'Token YOUR_API_KEY'. Through Jentic, the key is stored in the encrypted vault and never enters an agent's context.
Can I send a newsletter through the Buttondown API?
Yes. POST to /emails creates a new newsletter email; PATCH to /emails/{id} updates a draft. The API supports the full draft, edit, and send lifecycle for newsletter content.
What are the rate limits for the Buttondown API?
Buttondown does not publish hard rate limits in the spec. For batch subscriber syncs, space requests at a moderate cadence and watch for 429 responses; back off when they appear rather than retrying tight loops.
How do I add a subscriber through Jentic?
Run pip install jentic, then search Jentic with the query 'add a buttondown subscriber', load the schema for POST /subscribers, and execute with the email and any optional tag or metadata fields.
Can I look up a subscriber by email address?
Yes. GET /subscribers/{idOrEmail} accepts either the subscriber's UUID or their email address as the path parameter, returning the full subscriber record if it exists.
Can I limit what my agent is allowed to do with the Buttondown API?
Yes. Because you run Jentic One yourself, your own rules decide which Buttondown operations and credentials the agent may use. You can grant it read and create calls like GET /subscribers/{idOrEmail} and POST /subscribers while withholding destructive ones such as deleting a subscriber or removing an email draft. Since the subscriber or email id sits in the URL path (/subscribers/{idOrEmail}, /emails/{id}), you can also pin the agent to specific records rather than the whole audience.
Know of an official OpenAPI document? Contribute it →
For Agents
Manage Buttondown newsletters: create and update subscribers, send and edit emails, and organise content with tags. Authenticate with a Token in the Authorization header.
Use for: I need to add a new subscriber to my Buttondown newsletter, Find a subscriber by email address, Send a draft newsletter to my list, List all emails sent in the last 30 days
Not supported: Does not handle SMS, transactional email delivery for product flows, or marketing automation journeys - use for newsletter subscriber, email, and tag management only.
Jentic publishes the only available OpenAPI specification for Buttondown API, keeping it validated and agent-ready. Buttondown is a minimalist newsletter platform built for writers, indie creators, and small publications. This spec covers programmatic management of subscribers, emails, and tags - the core resources needed to drive a newsletter from outside the Buttondown UI. Authentication uses a token-based API key passed in the Authorization header.