Features
Email inbox API designed for AI agents, giving them mailboxes they can use programmatically. A related service, myagent.mx, is described as free email for AI agents. No further feature detail is published on the source page.
Sendmux
Email inbox API that gives AI agents their own mailboxes
Intermediate API
What is Sendmux?
Sendmux is an email inbox API for AI agents from founder Roshan Jonnalagadda, who also points to myagent.mx for free agent email. Public details are limited to a founder profile and blog posts.
Sendmux is an email inbox API built for AI agents. It is one of several products run by Roshan Jonnalagadda, an AI operator who describes a small, AI-augmented team scaling more than five businesses. The only public description of Sendmux comes from his personal site, where it is introduced as an email inbox API aimed at agents rather than people, so the details below stay close to what that source states. The core idea is that software agents increasingly need to send, receive and track email on their own, and a conventional mailbox designed for a human is an awkward fit. An inbox API treats the mailbox as something a program can call. An agent can use it as its working address for correspondence, instead of borrowing a person's account. The same site also points to myagent.mx, which it describes as free email for AI agents, suggesting a no-cost way to get an agent an address. The audience is developers and operators who build or run AI agents and want email as a channel those agents can use directly. The homepage is a founder blog, not a product site, so it publishes no feature list, pricing table, documentation or integration catalogue for Sendmux. Posts on the site mention that the team shipped a major Sendmux feature in a single morning, which gives a sense of how actively it is developed, but they do not describe the feature. In the wider market, Sendmux sits between transactional email services, which focus on outbound delivery, and ordinary hosted mailboxes, which assume a human at the keyboard. Its distinguishing position is the agent-first inbox. Anyone evaluating it should expect to confirm capabilities, limits and terms directly with the vendor, since the available material is a founder profile and operating essays rather than product documentation. The same founder also runs Qubrics.ai, Spotzee.com and Gotta.blog.
How do you use Sendmux?
1Read the founder profile
Start on the homepage to see how Sendmux is described: an email inbox API for AI agents, alongside the founder's other products.2Check the about page
Open the about page for background on the founder and the team behind Sendmux, and for ways to get in touch.
3Review the operating essays
Read the post on running five businesses with a small team to understand how Sendmux fits into the wider company.
4Try free agent email
The homepage points to myagent.mx for free email for AI agents, a low-commitment way to test an agent with its own address.5Confirm API details with the vendor
Because no documentation is published on the homepage, verify endpoints, limits and terms with Sendmux before relying on it.
Pros and cons
Pros
- Purpose-built for AI agents, so mailboxes are programmable rather than tied to a human accountAI
- Free email for agents is offered through the related myagent.mx serviceAI
- Run by a founder who publicly documents how a small team operates several AI businessesAI
- Actively developed, with a major Sendmux feature described as shipped by the teamAI
Cons
- The source is a personal blog, so there is no public feature list, documentation or API reference to reviewAI
- Pricing, usage limits and plan details are not published in the available materialAI
- No integrations or supported agent frameworks are namedAI
- Support channels and service guarantees are not described, which matters for production emailAI
How much does Sendmux cost?
Frequently asked questions about Sendmux
Does Sendmux have an API?
Yes, Sendmux offers an API.How do you use Sendmux?
The walkthrough on this page covers 5 steps: 1. Read the founder profile 2. Check the about page 3. Review the operating essays 4. Try free agent email 5. Confirm API details with the vendor.What platforms does Sendmux support?
Sendmux is available on Web App.What are the limitations of Sendmux?
The source is a personal blog, so there is no public feature list, documentation or API reference to review. Pricing, usage limits and plan details are not published in the available material. No integrations or supported agent frameworks are named.
