openagent.email vs Sendmux
55 fields both were evaluated on, 25 of them different — including where one discloses something the other does not. Every value links to the document it came from. 30 further fields are disclosed by neither and are listed at the end rather than tabled.
Assurance
| Field | openagent.email | Sendmux |
|---|---|---|
| Audit trail· | no public information openagent.email · checked Aug 2, 2026 | |
| Explainability· | “Every message comes back with codes and action links already extracted — and the raw text and HTML right there when extraction isn't enough.”openagent.email · checked Aug 2, 2026 | no public information sendmux.ai · checked Aug 7, 2026 |
| Runtime governance· | “Per-identity send rate limits (20/hour default) and automatic retention (30 days default).”openagent.email · checked Aug 2, 2026 | “Quotas at four levels: per-second, minute, hour, and day.”sendmux.ai · checked Aug 7, 2026 |
| Permission scopes· | “Every identity gets its own oa_… token that can only read and send as that address. Your admin key never touches an agent.”openagent.email · checked Aug 2, 2026 | “Inbox-scoped API keys Issue keys that can read and send for one mailbox, and nothing else.”sendmux.ai · checked Aug 7, 2026 |
| Outcome-based pricing· | no paid tier, no usage limits, no per-inbox pricing “openagent.email is open source under the Apache-2.0 license — no paid tier, no usage limits, no per-inbox pricing.”openagent.email · checked Aug 2, 2026 Not in our latest capture. We captured this page again on Sep 17, 2026 and this quote was not there. How we re-check citations | no public information sendmux.ai · checked Aug 7, 2026 |
| SLA terms· | no public information openagent.email · checked Aug 2, 2026 | “Need dedicated infrastructure, SLAs, or volume pricing? Talk to us about enterprise”sendmux.ai · checked Aug 7, 2026 |
Agency
| Field | openagent.email | Sendmux |
|---|---|---|
| Action space· | read and send “Every identity gets its own oa_… token that can only read and send as that address.”openagent.email · checked Aug 2, 2026 | “Create agent inboxes, send through your providers, and route with quotas, weighted delivery, and failover from one API.”sendmux.ai · checked Aug 7, 2026 |
| Operating environment· | no public information openagent.email · checked Aug 2, 2026 | |
| Initiative· | “The agent waits on the inbox; the signup mail arrives; the OTP comes back parsed and ready to type.”openagent.email · checked Aug 2, 2026 | no public information sendmux.ai · checked Aug 7, 2026 |
Safety
| Field | openagent.email | Sendmux |
|---|---|---|
| Usage restrictions· | “Per-identity send rate limits (20/hour default) and automatic retention (30 days default). A leaked token can't become a spam cannon.”openagent.email · checked Aug 2, 2026 Not in our latest capture. We captured this page again on Sep 17, 2026 and this quote was not there. How we re-check citations | no public information sendmux.ai · checked Aug 7, 2026 |
| Data handling· | Message bodies are never stored; automatic 30-day retention by default. “Message bodies are never stored.”openagent.email · checked Aug 20, 2026 | no public information sendmux.ai · checked Aug 7, 2026 |
Practicality
| Field | openagent.email | Sendmux |
|---|---|---|
| Pricing model· | no paid tier, no usage limits, no per-inbox pricing “openagent.email is open source under the Apache-2.0 license — no paid tier, no usage limits, no per-inbox pricing.”openagent.email · checked Aug 2, 2026 Not in our latest capture. We captured this page again on Sep 17, 2026 and this quote was not there. How we re-check citations | “Pay for what you use. Nothing else. No per-seat fees. No per-mailbox fees. No minimum commitments. Pay only when billable usage begins.”sendmux.ai · checked Aug 7, 2026 Not in our latest capture. We captured this page again on Sep 17, 2026 and this quote was not there. How we re-check citations |
| Price point· | $5/mo VPS “The only thing you pay for is the server you run it on, and a $5/mo VPS is enough.”openagent.email · checked Aug 2, 2026 | “$0.15/1k recipients | No subscriptions | Free to start”sendmux.ai · checked Aug 7, 2026 Not in our latest capture. We captured this page again on Sep 17, 2026 and this quote was not there. How we re-check citations |
| Availability· | open source “openagent.email is open source under the Apache-2.0 license”openagent.email · checked Aug 2, 2026 Not in our latest capture. We captured this page again on Sep 17, 2026 and this quote was not there. How we re-check citations | “Free to start · No credit card required”sendmux.ai · checked Aug 7, 2026 Not in our latest capture. We captured this page again on Sep 17, 2026 and this quote was not there. How we re-check citations |
| Deployment options· | “HTTP API and SMTP on port 587. Drop-in compatible with any agent framework you’re already using.”sendmux.ai · checked Aug 7, 2026 | |
| Integrations· | “WORKS WITH ANY MCP CLIENT — AND ANYTHING THAT CAN CURL Claude Code Cursor Windsurf Docker ✦ Kimi Code ✦ Any MCP client ✦ Plain REST”openagent.email · checked Aug 2, 2026 | “Connect Gmail, SendGrid, Mailgun, Resend, or any SMTP-compatible provider.”sendmux.ai · checked Aug 7, 2026 |
| Supported regions· | no public information openagent.email · checked Aug 2, 2026 |
Ecosystem
| Field | openagent.email | Sendmux |
|---|---|---|
| Protocols supported· | ||
| Tool use· | “MCP tools mail_new_identity mail_list_identities mail_list_messages mail_read_message mail_wait_for mail_send mail_mark_seen”openagent.email · checked Aug 2, 2026 | “your agent now has Mailbox, Sending + Management tools”sendmux.ai · checked Aug 7, 2026 |
| Multi-agent· | Yes — supports agent-to-agent task threads (email-backed) with an A2A-vocabulary Agent Card “Agent-to-agent tasks Email-backed task threads with server-stamped states”openagent.email · checked Aug 13, 2026 | |
| API access· | “REST API POST /v1/identities — mint an address + scoped token GET /v1/identities — list every identity you own POST /v1/identities/:a/token — rotate (revoke) a token DELETE /v1/identities/:a — retire an identity GET /v1/messages — list an inbox GET /v1/messages/:id — full mail + parsed OTP POST /v1/messages/wait — long-poll for new mail POST /v1/messages/:id/seen — mark read / unread POST /v1/send — send as any identity you own”openagent.email · checked Aug 2, 2026 Not in our latest capture. We captured this page again on Sep 17, 2026 and this quote was not there. How we re-check citations | |
| Open source· | “open source under the Apache-2.0 license”openagent.email · checked Aug 2, 2026 Not in our latest capture. We captured this page again on Sep 17, 2026 and this quote was not there. How we re-check citations | no public information sendmux.ai · checked Aug 7, 2026 |
| Marketplace presence· | no public information openagent.email · checked Aug 2, 2026 |
Impact
| Field | openagent.email | Sendmux |
|---|---|---|
| Deployment scale· | open source under the Apache-2.0 license — no paid tier, no usage limits, no per-inbox pricing. “openagent.email is open source under the Apache-2.0 license — no paid tier, no usage limits, no per-inbox pricing.”openagent.email · checked Aug 2, 2026 Not in our latest capture. We captured this page again on Sep 17, 2026 and this quote was not there. How we re-check citations | |
| Target sectors· | no public information openagent.email · checked Aug 2, 2026 | “Platform builders Scale from one agent to thousands. Built for companies running email for their customers' agents.”sendmux.ai · checked Aug 7, 2026 |
Disclosed by neither
Both openagent.email and Sendmux publish nothing on these 30 fields. That is a finding about the category rather than a difference between them, so it is recorded here instead of as 30 identical table rows. Each is shown with its source check on the individual profiles.
- Autonomy level
- Human oversight
- Goal complexity
- User base
- High-risk domains
- Documented incidents
- Support model
- Base models
- Model provider
- Model swappable
- Open weights
- Fine-tuning
- Context window
- Safety evaluations
- Red teaming
- Safety policy
- Model or system card
- Incident reporting
- Third-party evaluations
- Insurance available
- Insurance carriers
- Coverage limits
- Indemnification
- Liability cap
- Tamper-evident log
- Compliance certifications
- Regulatory alignment
- Settlement mechanism
- Dispute process
- Evaluation coverage
Questions
- How do openagent.email and Sendmux compare on data handling?
- openagent.email: Message bodies are never stored; automatic 30-day retention by default.. Sendmux: no public information disclosed.
- How do openagent.email and Sendmux compare on outcome-based pricing?
- openagent.email: no paid tier, no usage limits, no per-inbox pricing. Sendmux: no public information disclosed.