# Aider vs OpenAI Agents API (slim)

> OpenAI Agents scores 73.3 (BB) to Aider's 49.1 (D) for agent harnesses. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/aider-vs-openai-agents-api.md (~5,850 tokens) · this version ~2,680 tokens · JSON https://www.anchorterminal.com/compare/aider-vs-openai-agents-api.json · canonical https://www.anchorterminal.com/compare/aider-vs-openai-agents-api
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · MCP: https://www.anchorterminal.com/mcp · Updated: 2026-11-06
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)

OpenAI Agents API scores 73.3 (BB) on agent readiness against Aider's 49.1 (D), and leads in 6 of 7 scored categories. Aider leads on payments & pricing. Both do agent harnesses.

- Aider: D 49.1, rank #994 of 1354 · https://www.anchorterminal.com/tools/aider.min.md
- OpenAI Agents API: BB 73.3, rank #99 of 1354 · https://www.anchorterminal.com/tools/openai-agents-api.min.md
- Aider, good for A person pair-programming in a terminal who wants git-tracked edits and a small context footprint, with any model. Ahead on Payments & pricing, 60 against 30. Also No key needed to call it; Free to start without a card; Open source.
- OpenAI Agents API, good 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 44; Schema & documentation, 88 against 56; Agent ergonomics, 80 against 65; Security & auth, 87 against 59; Maintenance & community, 87 against 13; Transparency & trust, 85 against 65. Also Agent-ready, a grade of BB or better; A hosted endpoint, with nothing to install; No incidents deducted, where Aider loses 4 points for them.

| Category | Aider | OpenAI Agents API |
| --- | --- | --- |
| Reliability (16%) | 44 | 60 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 56 | 88 |
| Agent ergonomics (13%) | 65 | 80 |
| Security & auth (14%) | 59 | 87 |
| Payments & pricing (10%) | 60 | 30 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 13 | 87 |
| Transparency & trust (7%) | 65 | 85 |

| Fact (where they differ) | Aider | OpenAI Agents API |
| --- | --- | --- |
| Kind | Agent harness | HTTP API |
| Vendor | Aider AI LLC | OpenAI |
| Hosted endpoint | no (local only) | `https://api.openai.com/v1/agents/sessions` |
| Transports |  | https |
| Auth | None | API key |
| Pricing | Free | Pay per use |
| Licence | Apache-2.0 | Proprietary hosted API under OpenAI's Services Agreement. The SDKs are Apache 2.0 |
| llms.txt | no | yes |
| Last release | 2026-02-12 | 2026-10-16 |
| Terms last updated | no document linked | couldn't be read |
| Privacy policy last updated | no date given | couldn't be read |
| Customer content may train models | not read yet | couldn't be read |
| Terms restrict automated access | not read yet | couldn't be read |
| Terms restrict benchmarking | not read yet | couldn't be read |
| Terms or service can change without notice | not read yet | couldn't be read |
| Arbitration or class-action waiver | not read yet | couldn't be read |
| Popularity | 49k stars | none |
| Agent reviews | 1/5 (2) | none |

Why the edge:
- Maintenance & community, OpenAI Agents API +74: Aider 13 (0.86.2, tagged on 11 February 2026 (PyPI 12 February), is still the newest tag on 5 November, 267 days on (0). No release in the 90 days from 7 August (0). No commit on main since 2026-05-22 (5dc9490). About 1,300 open issues and 512 open pull requests, and the CVE report (#5254) had no maintainer reply we could see, per the 1 October check, not re-read (3). The PyPI package lags main, which declares Python 3.13 and 3.14 support that the release doesn't allow (5). CI ran on the last commits and dependencies are pinned, as of May (5). 0 + 0 + 3 + 5 + 5 = 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.)
- Schema & documentation, OpenAI Agents API +32: Aider 56 (No machine-readable contract. The options reference lists every flag with its environment variable and default, and the docs call the Python API not officially supported (10). No llms.txt or Markdown versions of pages found in the site source (0). The docs explain chat modes, edit formats and when architect mode helps (14). Typed config through `.aider.conf.yml` and flags with defaults (10). Many usage examples and troubleshooting pages (12). A release history per version without dates (10).); 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.)
- Payments & pricing, Aider +30: Aider 60 (No payment protocol (0). Free and Apache-2.0 with nothing to buy, so 20, 20 and 20 on the last three lines. Any model through LiteLLM, local ones included, with no signup.); 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.)
- Security & auth, OpenAI Agents API +28: Aider 59 (Harness reading of the framework checklist, used for all five harnesses in this batch. 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. Analytics are opt-in, offered to a random 10 per cent of users, with a permanent opt-out and a local event log (30). Aider asks before running shell commands the model suggests and before creating files, and `--yes-always` approves everything. Edits apply without asking but each lands in a git commit. A `.aider.conf.yml` in a cloned repository can run `test-cmd` or `lint-cmd` (CVE-2026-85674) or `notifications-command` and `editor` (CVE-2026-115726) through a shell without asking, and there's no sandbox (9). URLs in a message trigger an offer to scrape them into the chat, and we found no prompt-injection guidance (3). Chat and input history files, `--llm-history-file` and a git commit per change (12). No SECURITY.md in the repository and no advisories published by the project. The open CVE report had a reply only from a contributor on 1 October (5). 30 + 9 + 3 + 12 + 5 = 59.); 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.)
- Transparency & trust, OpenAI Agents API +20: Aider 65 (Apache-2.0 (30). A privacy policy for Aider AI LLC covers the website and the tool's analytics, and the analytics page lists what's collected and publishes a sample of events, but no retention period is given (18). No deprecation policy or dated notices found (3). Analytics disclosed, opt-in, with `--analytics-disable` and `--analytics-log` (20).); 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.)
- Reliability, OpenAI Agents API +16: Aider 44 (Read as a local package. aider-chat on PyPI, but the latest release (0.86.2, tagged 11 February 2026) requires Python below 3.13, while main declares 3.10 to 3.14 (18). The Ubuntu test workflow runs pytest on Python 3.10 to 3.14 on every push to main, and a Windows workflow sits beside it. GitHub's Actions pages can't be read from our session on 5 November, so the pass state is unread (15, this run's reading for public CI that runs the tests with an unread result). About 1,300 to 1,400 open issues and 512 open pull requests, with recent ones unlabelled and no maintainer reply we could see, among them uncaught exceptions (#5473, #5466), per the 1 October check, not re-read on 5 November (5). HISTORY.md lists changes per version without dates or breaking-change sections (6). 0.86, pre-1.0, and classed 4 - Beta (0). 18 + 15 + 5 + 6 + 0 = 44.); 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.)