Head to head · Agent harnesses · October 2026 research run

OpenAI Agents API vs Verdent

OpenAI Agents API scores 73.3 (BB) on agent readiness against Verdent's 39.7 (E), and leads in every scored category. Both do agent harnesses.

Best agent harnesses and coding agents · All 1500 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

  • Reliability, 60 against 43
  • Schema & documentation, 88 against 55
  • Agent ergonomics, 80 against 35
  • Security & auth, 87 against 33
  • Payments & pricing, 30 against 20
  • Maintenance & community, 87 against 61
  • Transparency & trust, 85 against 55

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

Verdent E

Best for A person who wants a desktop app to plan and run several coding tasks at once, possibly on their own Claude Code or Codex.

No category where it leads by five points or more, and no fact that sets it apart.

Watch for

No CLI, print mode, API or SDK, so a pipeline can't start or read a run except through a paired chat bot

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 +54

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.

Verdent 33

Framework reading (telemetry defaults, approvals, guardrails, sandboxing). Conversation history and tool results go to Verdent's US servers and on to Azure, Bedrock or Vertex, with zero data retention stated for Vertex and Bedrock only. Event logging to log.verdent.ai has no documented opt-out. BYOA keys stay on the machine (10). Plan Mode is read-only, Agent Mode asks before destructive commands and edits outside scope, and workers are isolated by git worktree, but there is no sandbox or network control and the approval list isn't enumerated (9). No prompt-injection guidance found, while web search and fetch results enter the context (2). Usage history in the dashboard, no audit log found (5). A security page with a disclosure address and a five-day acknowledgement, SOC 2 and ISO/IEC 42001 being pursued rather than held, no security.txt and no bug bounty (7). 10+9+2+5+7 = 33.

Agent ergonomics OpenAI Agents API +45

OpenAI Agents API 80

Read as an API an agent drives. Context is compacted automatically, and session budgets and streamed events keep output sized (20 of 25). Sessions can be listed, continued and steered, events streamed or sent by webhook, artifacts fetched (15 of 20). Actionable error codes with recovery steps (20). No idempotency key; a documented check-then-retry procedure (10 of 20). One session call with defaults (medium sandbox, network enabled), SDKs in five languages (15). 20 + 15 + 20 + 10 + 15 = 80.

Verdent 35

Harness reading. MCP servers per project or globally, subagents, skills and rules, but no per-tool disabling or deferred loading found (10). No output-size, turn-limit or budget controls for a run were found beyond credit balances (5). No exit codes or error format, since there is no headless mode (3). Parallel workers in git worktrees and a review column make runs reviewable and reversible, with no resume by ID documented (10). No CLI, API or SDK. A pipeline can only reach Manager through a paired Telegram, Slack or Feishu bot (7). 10+5+3+10+7 = 35.

Schema & documentation OpenAI Agents API +33

OpenAI Agents API 88

The reference is linked from the overview and the SDKs carry beta.agents types; we didn't confirm /agents/sessions in OpenAI's public OpenAPI file, so 15 of 25. llms.txt with every Agents API page and Markdown twins (10). The overview, architecture page and the agents guide that compares the Agents API, Agents SDK and Responses API say when to use it (20). Typed configuration with enumerated container sizes, network modes and environment types (13 of 15). Examples in six languages and an errors page with codes per HTTP status, turn and session (15). Dated changelog entries and a versioned beta header (15). 15 + 10 + 20 + 13 + 15 + 15 = 88.

Verdent 55

Framework reading for a harness. No schema for settings or output, only mcp.json examples in the standard mcpServers shape (5). Every current docs page has a Markdown twin at the same path with .md, though no llms.txt (10). The docs say when to use Agent Mode or Plan Mode and what Plan Mode can't do, but the Agent Mode page lists the actions that need approval only as "certain tool executions" and "destructive operations" (12). Modes and BYOA agent types are enumerated, permissions are not (5). Examples on the MCP, BYOA and messaging pages, and a recovery page, with no error codes (8). Version numbers and a dated public changelog (15). The archived 1.0 docs are still served beside the current ones. 5+10+12+5+8+15 = 55.

Transparency & trust OpenAI Agents API +30

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.

Verdent 55

Proprietary, under terms from Verdent AI, Inc. that are clear on use and ownership (15). The privacy policy and security page agree that data stays in the US and that input isn't trained on without consent, and the security page lists subprocessors. The privacy policy gives no retention periods, names MiniMax as a provider the security list leaves out, and deletion is by email request (14). The credit bonus carries a promise of 15 days' notice, but Free Mode was retired on the day v2.18.0 shipped and no deprecation policy was found (6). Subprocessors and their locations are listed, and the domains the app calls are named, with event logging undescribed (12). 15+14+6+12 = 47.

Maintenance & community OpenAI Agents API +26

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.

Verdent 61

Closed service. v2.18.0 on 29 October 2026, eight days before this check (30). More than three dated releases in the 90 days from 8 August, among them 2.10.0 to 2.18.0 (20). A dated public changelog, a support address, Discord and a subreddit, with no public tracker to read reply times (8). No official SDK or MCP server to keep current (0). No public packages or CI to judge (3). 30+20+8+0+3 = 61.

Reliability OpenAI Agents API +17

OpenAI Agents API 60

Read as a hosted API. status.openai.com has an Agents component under APIs (20). Since release on 10 September (57 days, not 90), the feed names the Agents API in a degraded-performance incident on 14 September, the elevated errors across ChatGPT, Codex and the API on 29 September (the openai-api listing reads that one as a major, 17:52 to 23:14 UTC), computer use issues and degraded workspace agents on 6 and 7 October, degraded performance across the APIs for 22 minutes on 21 October, and overbilling for hosted containers on 19 September. One major, the rest minor (10). Rate limits come from the shared guide, published per tier and model with headers, and the errors page adds a Files API allowance on session creation (15). 429 and 503 guidance with Retry-After, capped backoff and a check-then-retry procedure for turns (15). The Scale Tier SLA in the openai-api listing isn't shown to cover a beta API (0). Public beta behind the agents=v1 header (0). 20 + 10 + 15 + 15 + 0 + 0 = 60.

Verdent 43

Local-package reading, as for the other closed-source harnesses. The desktop app installs from verdent.ai with macOS 11 or later and 64-bit Windows 10 and 11 stated, and the extension from the editor marketplaces, but not from a package registry (15). No public CI or test suite, since the source isn't published (0). No public issue tracker, every task runs through Verdent's servers, and no status page was found, so there is no readable record (5). A dated changelog by version, with the end of Free Mode called out in v2.18.0, but no breaking-change sections (8). 2.18.0, generally available (15). 15+0+5+8+15 = 43.

Score by category

CategoryWeight this runOpenAI Agents APIVerdentEdge
Reliability16%206043OpenAI Agents API +17
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28855OpenAI Agents API +33
Agent ergonomics13%16.28035OpenAI Agents API +45
Security & auth14%17.58733OpenAI Agents API +54
Payments & pricing10%12.53020OpenAI Agents API +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88761OpenAI Agents API +26
Transparency & trust7%8.88555OpenAI Agents API +30
Negative events≤150-2
TotalBB 73.3/100E 39.7/100

Facts side by side

FactOpenAI Agents APIVerdent
KindHTTP APIAgent harness
VendorOpenAIVerdent AI, Inc.
Hosted endpointhttps://api.openai.com/v1/agents/sessionsno (local only)
Transportshttps
AuthAPI keyOAuth or key
PricingPay per usePaid
x402nono
LicenceProprietary hosted API under OpenAI's Services Agreement. The SDKs are Apache 2.0Proprietary. The terms of use from Verdent AI, Inc. forbid reverse engineering or copying any component, and no source is published
Read-only variant documentednoyes
llms.txtyesno
Last release2026-10-162026-10-29
Terms last updatedcouldn't be read2026-05-25
Privacy policy last updatedcouldn't be read2026-05-26
Customer content may train modelscouldn't be readyes
Terms restrict automated accesscouldn't be readyes
Terms restrict benchmarkingcouldn't be readnot found in the text
Terms or service can change without noticecouldn't be readyes
Arbitration or class-action waivercouldn't be readnot found in the text

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.

Verdent

A desktop and editor coding agent that splits a goal into parallel workers in git worktrees, with a read-only Plan Mode, MCP servers and the option to run workers on Claude Code or Codex. It has no CLI, API or sandbox, sends context through Verdent's servers, and has had no free tier since 29 October 2026.

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

Verdent

  1. Don't plan to drive Verdent headless. Hand the task to the person using the desktop app, or use a harness with a print mode
  2. Start large changes in Plan Mode and review plan.md before switching to Agent Mode
  3. Add MCP servers in the project's .mcp.json or ~/.verdent/mcp.json in the mcpServers shape
  4. Keep work under git, since rollback relies on git and there is no sandbox
  5. Budget in credits at about $0.059 each, because there is no free allowance since 29 October 2026

Questions

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

OpenAI Agents API scores 73.3 (BB) on agent readiness against Verdent's 39.7 (E), and leads in every scored category.

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

OpenAI Agents API has a hosted endpoint at https://api.openai.com/v1/agents/sessions. No hosted endpoint is listed for Verdent.

Other comparisons with OpenAI Agents API or Verdent

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