Head to head · Agent harnesses · October 2026 research run

OpenAI Agents API vs OpenMausBot

OpenAI Agents API scores 73.3 (BB) on agent readiness against OpenMausBot's 65.4 (B), and leads in 4 of 7 scored categories. OpenMausBot leads on payments & pricing. Both do agent harnesses.

Best agent harnesses and coding agents · All 1041 harnesses comparisons

Which one, for what

OpenAI Agents API BB

Best for Teams that want OpenAI to run the agent loop, with sandboxes, MCP tools and subagents, and are fine with a beta API, US-only data residency and no Zero Data Retention.

Ahead on

  • Security & auth, 87 against 59
  • Maintenance & community, 87 against 74
  • Transparency & trust, 85 against 59

Also in its favour

  • Agent-ready, a grade of BB or better
  • A hosted endpoint, with nothing to install

Watch for

Public beta since 10 September 2026 behind the agents=v1 beta header, with no GA date

OpenMausBot B

Best for A person or an outside agent who wants several CLI agents (Claude Code, Codex, Grok, ACP CLIs) organised as named bots with their own computers, routines and approvals, driven by MCP or a CLI.

Ahead on

  • Payments & pricing, 50 against 30

Also in its favour

  • Runs on your own machine
  • Free to start without a card
  • Open source

Watch for

New bots start at Full access, which approves provider permission requests without a card

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Security & auth OpenAI Agents API +28

OpenAI Agents API 87

Project keys with restricted per-endpoint permissions, service accounts and workload identity, per the openai-api listing; we didn't confirm a key can be limited to /v1/agents (27 of 30). Automatic review for approvals, a sandbox network restricted to a host allowlist, vaults for secrets and a sandbox security guide (17 of 20). The agent reads web pages, MCP results and browser content; the sandbox security guide and approval flow are the mitigations, with no prompt-injection guide of its own found (8 of 15). Tracing, observability and usage per session and admin audit logs (15). SOC 2 Type 2, ISO 27001 family, Bugcrowd bounty and a disclosure policy, per the openai-api listing (20). Not ZDR-eligible and US residency only, recorded under transparency. 27 + 17 + 8 + 15 + 20 = 87.

OpenMausBot 59

Harness reading of the framework checklist, as for the other harnesses. 30 for what leaves the machine by default, 20 for approvals and sandboxing, 15 for prompt-injection posture, 15 for audit and 20 for the security programme. The harness binds to loopback and keys stay in ~/.openmausbot, but PostHog usage analytics are on until switched off, with a daily snapshot of what is set up, and the CLI guide says API keys are saved in plaintext with mode 0600 (18). Approval cards for provider permission requests, a narrow Always allow, isolated Local VMs and cloud computers, own-computer control off by default, and an MCP server that cannot approve, delete or touch credentials. New bots start at Full access, bot changes to skills, profiles and team setup apply without approval, and new bots keep every connected-app tool until grants are assigned (10). The docs say web page instructions never authorise credential use and that one-time codes go only to the site that sent them, and imported bots arrive with no grants, but bots read one-time codes from connected email without asking again (9). Per-thread NDJSON event logs, an Inspector, a decision log for connected-app grants and Undo lines for bot changes (12). SECURITY.md with an email, GitHub private vulnerability reporting enabled and scope notes that name one open risk. No published advisories, security.txt or bug bounty. npm releases use trusted publishing with provenance, and the Windows installer is unsigned (10).

Transparency & trust OpenAI Agents API +26

OpenAI Agents API 85

Closed service with clear terms, Apache-2.0 SDKs (15). Session state retained until deleted, deletable sessions and artifacts, not ZDR-eligible, US residency only, and the data-controls guide agrees; no retention period for artifacts after a sandbox expires (25 of 30). Dated deprecation notices with minimum periods for GA models; a beta API can change faster (15 of 20). Subprocessors and processing countries listed, per the openai-api listing (20). 15 + 25 + 15 + 20 = 75.

OpenMausBot 59

Apache 2.0 outside enterprise/, which is source-available and needs a licence key in production. Deleting the folder leaves the open-source edition, and a CI job builds it (27). The privacy policy of 18 October 2026 (re-read on 2 November, unchanged) names Supamaus Software Private Limited and separates the local apps from the optional hosted service, but it says the apps contain no third-party analytics SDKs while the app loads posthog-js by default, and hosted account data is kept while needed with no period stated (12). No deprecation policy. Dated release notes, and older installers kept in a legacy releases repository (4). docs/analytics.md lists every event and property and how to switch it off, but analytics are on by default and the privacy policy does not mention them for the apps (14).

Payments & pricing OpenMausBot +20

OpenAI Agents API 30

No machine payment protocol (0). Model, tool and container prices published without a login, and no fee for the API itself (20). The Free tier reading of the openai-api listing, half (10). Sign-up in a browser (0). 0 + 20 + 10 + 0 = 30.

OpenMausBot 50

No payment protocol (0). MausBot Cloud, the hosted option, is priced by plan on a public page ($15, $49 and $99 a month, Team $169 and Business $599, or Business self-hosted $299 a month billed yearly, re-read on 2 November), with extra computer-hours at $0.05 each, so plan pricing (10). The app is free with no card or account (20). npx openmausbot installs and starts it with no signup (20).

Maintenance & community OpenAI Agents API +13

OpenAI Agents API 87

Closed API. Last dated change 16 October 2026, Ultrafast mode and document skills (30). Four dated changelog entries in the 57 days since release, 10 September, 29 September, 9 October and 16 October (20). Changelog and help centre, as the openai-api listing reads them (12 of 15). Official SDKs carry beta.agents (15). SDK CI, per the openai-api listing (10). 30 + 20 + 12 + 15 + 10 = 87.

OpenMausBot 74

v0.1.137 on 1 November 2026, after v0.1.135 on 31 October and v0.1.136 on 1 November (30). 128 desktop versions from 11 August to 30 October 2026, and three more since (20). The maintainer has 4,221 commits and the contributor list returns at least 100 accounts. 587 issues and pull requests were open from about 3,940 filed on 30 October, when we could only sample the newest open issues, nearly all from the last two days and mostly unanswered so far (per the 30 October check; github.com refuses our requests on 2 November) (16). Not in the official MCP registry, which returns nothing for mausbot (0). CI on main runs on every push with most finished runs passing, npm provenance and an SBOM for the bundled Cua runtime (per the 30 October check) (8). 30+20+16+0+8 = 74.

Score by category

CategoryWeight this runOpenAI Agents APIOpenMausBotEdge
Reliability16%206060even
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28890OpenMausBot +2
Agent ergonomics13%16.28077OpenAI Agents API +3
Security & auth14%17.58759OpenAI Agents API +28
Payments & pricing10%12.53050OpenMausBot +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88774OpenAI Agents API +13
Transparency & trust7%8.88559OpenAI Agents API +26
Negative events≤150-2
TotalBB 73.3/100B 65.4/100

Facts side by side

FactOpenAI Agents APIOpenMausBot
KindHTTP APIAgent harness
VendorOpenAISupamaus Software Private Limited
Hosted endpointhttps://api.openai.com/v1/agents/sessionsno (local only)
Transportshttpsstdio
AuthAPI keyOAuth or key
PricingPay per useFreemium
x402nono
LicenceProprietary hosted API under OpenAI's Services Agreement. The SDKs are Apache 2.0Apache-2.0
Tools exposednone20
Read-only variant documentednono
llms.txtyesno
Last release2026-10-162026-11-01
Terms last updatedcouldn't be read2026-10-10
Privacy policy last updatedcouldn't be read2026-10-18
Customer content may train modelscouldn't be readnot found in the text
Terms restrict automated accesscouldn't be readnot found in the text
Terms restrict benchmarkingcouldn't be readnot found in the text
Terms or service can change without noticecouldn't be readnot found in the text
Arbitration or class-action waivercouldn't be readnot found in the text
Popularitynone8.2k stars, 3.5k npm/wk

Verdicts

OpenAI Agents API

OpenAI's hosted agent runtime, the Codex harness behind one session call, with MCP, functions, web search, computer use, subagents and sandboxes on OpenAI or your own infrastructure. Documentation, errors and SDKs are thorough. It's still public beta, can't use Zero Data Retention and keeps data in the United States only.

OpenMausBot

A bounded 20-tool MCP server with typed schemas, annotations and idempotent sends, and a headless CLI with JSON output and exit codes, let another agent hand work to a bot team and wait on it. New bots start at Full access, so provider permission requests pass without a card, and usage analytics stay on until switched off.

Before you call either

OpenAI Agents API

  1. POST https://api.openai.com/v1/agents/sessions with a project key and the header OpenAI-Beta: agents=v1, or use client.beta.agents in the SDKs
  2. Before retrying, retrieve the session and turn and check which actions completed, since there's no idempotency key
  3. Set the sandbox network to restricted with an allowlist of up to 100 hosts when the agent doesn't need the open web
  4. Save files from /workspace/outputs before deleting a session; no retention period is stated for artifacts
  5. Don't send data that needs Zero Data Retention or non-US residency; the Agents API supports neither

OpenMausBot

  1. Ask the owner for a pairing code from Settings > Phone, exchange it at POST /api/auth/pair, and set OPENMAUSBOT_TOKEN with an explicit OMB_PORT
  2. Pass a send_id with every send_bot_message and send_channel_message, so a retry returns the first receipt
  3. Use wait_for_conversation instead of polling, and on needs-user stop and tell the owner a card is waiting
  4. Check a bot's access level with the owner before sending work. New bots run at Full access unless defaults were changed
  5. Ask the owner to switch off Settings > General > Usage analytics if nothing beyond model calls should leave the machine

Questions

Which is better for AI agents, OpenAI Agents API or OpenMausBot?

OpenAI Agents API scores 73.3 (BB) on agent readiness against OpenMausBot's 65.4 (B), and leads in 4 of 7 scored categories. OpenMausBot leads on payments & pricing.

Can an agent call OpenAI Agents API and OpenMausBot without installing anything?

OpenAI Agents API has a hosted endpoint at https://api.openai.com/v1/agents/sessions. OpenMausBot runs on your own machine, with no hosted endpoint listed.

Are OpenAI Agents API and OpenMausBot open source?

No open-source release is listed for OpenAI Agents API. OpenMausBot is open source (Apache-2.0).

Other comparisons with OpenAI Agents API or OpenMausBot

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