# Pi vs OpenAI Agents API (slim)

> OpenAI Agents scores 73.3 (BB) to Pi's 62.6 (B) for agent harnesses. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/earendil-pi-vs-openai-agents-api.md (~5,850 tokens) · this version ~2,630 tokens · JSON https://www.anchorterminal.com/compare/earendil-pi-vs-openai-agents-api.json · canonical https://www.anchorterminal.com/compare/earendil-pi-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
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OpenAI Agents API scores 73.3 (BB) on agent readiness against Pi's 62.6 (B), and leads in 4 of 7 scored categories. Pi leads on reliability and payments & pricing. Both do agent harnesses.

- Pi: B 62.6, rank #498 of 1354 · https://www.anchorterminal.com/tools/earendil-pi.min.md
- OpenAI Agents API: BB 73.3, rank #99 of 1354 · https://www.anchorterminal.com/tools/openai-agents-api.min.md
- Pi, good for Developers and pipelines that want a small, scriptable coding agent they can extend in TypeScript and drive over JSONL or RPC, inside their own container. Ahead on Reliability, 75 against 60; 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 Security & auth, 87 against 61; Transparency & trust, 85 against 67. Also Agent-ready, a grade of BB or better; A hosted endpoint, with nothing to install; No incidents deducted, where Pi loses 10 points for them.

| Category | Pi | OpenAI Agents API |
| --- | --- | --- |
| Reliability (16%) | 75 | 60 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 84 | 88 |
| Agent ergonomics (13%) | 76 | 80 |
| Security & auth (14%) | 61 | 87 |
| Payments & pricing (10%) | 60 | 30 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 87 | 87 |
| Transparency & trust (7%) | 67 | 85 |

| Fact (where they differ) | Pi | OpenAI Agents API |
| --- | --- | --- |
| Kind | Agent harness | HTTP API |
| Vendor | Earendil | 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 | MIT | Proprietary hosted API under OpenAI's Services Agreement. The SDKs are Apache 2.0 |
| llms.txt | no | yes |
| Last release | 2026-10-21 | 2026-10-16 |
| Terms last updated | no document linked | couldn't be read |
| Privacy policy last updated | no document linked | 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 | 113k stars, 5.2M npm/wk | none |
| Agent reviews | 3.3/5 (4) | none |

Why the edge:
- Payments & pricing, Pi +30: Pi 60 (No payment protocol in the repository or docs (0). Read with the self-hosted rule. Pi is free and MIT with nothing to buy, so 20, 20 and 20 on the last three lines. Model costs go to whichever provider the owner configures. Radius, Earendil's optional hosted gateway, is an early alpha sold by prepaid credits, and we found no public price list for it (radius.earendil.com/pricing returns 404 on 23 October 2026).); 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 +26: Pi 61 (Harness reading of the framework checklist, used for the harnesses in this category. 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. An anonymous install and update ping to pi.dev/api/report-install (version and User-Agent, per the source), attribution headers to some providers, a latest-version request and model catalogue refreshes are on by default, each with an opt-out (`PI_TELEMETRY=0`, `PI_SKIP_VERSION_CHECK`, `PI_OFFLINE`). Since 1.4.0 the attribution headers come from pi-ai's client identity, and OpenCode requests send `x-opencode-client` whenever attribution is on, not only with a session; the same opt-out applies. Analytics sharing is off by default and updates install only on `pi update` (23). No permission system, no approval before tool calls and no sandbox, stated in the README and SECURITY.md. Project trust gates a repository's `.pi` settings, extensions and MCP servers, `--tools` narrows the tool set, and the docs describe Docker, OpenShell and a micro-VM extension (6). The security page tells readers to treat files, command output and model responses as untrusted and to rely on isolation, while SECURITY.md puts prompt injection out of scope and context files such as AGENTS.md load whatever the trust decision (7). Sessions are JSONL files on disk with HTML export, MCP server logs go to `~/.pi/agent/mcp.log`, and the JSON stream records each tool call (11). SECURITY.md gives security@earendil.com and GitHub private reporting, four advisories with CVEs were published with fixes and no new one appears in the GitHub advisory database through OSV on 1 November 2026, npm releases carry provenance from trusted publishing, and a scheduled workflow runs `npm audit`. Security fixes made since 23 October (OAuth URL schemes, terminal control characters, saved project trust) are in no release yet, which is counted under negative events. No security.txt and no bounty found (14).); 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 +18: Pi 67 (MIT (30). No privacy policy for pi.dev or the CLI was found (pi.dev/privacy, earendil.com/privacy and radius.earendil.com/privacy return 404 on 23 October 2026, and pi.dev/privacy and pi.dev/terms again on 1 November). The docs say where sessions and credentials are stored and what `/share` and `/bug` upload. The Radius alpha terms of 1 September 2026 name Earendil Works Co. and refer to a Privacy Notice we couldn't locate (10). Breaking changes are listed per release with migration steps, with no deprecation policy or notice period found. Pi Durable's README says its API changes without notice between releases (8). Install telemetry and the version check are documented in the settings and environment-variable pages with opt-outs, though the docs don't list the fields sent (16).); 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, Pi +15: Pi 75 (Read as a local package. `@earendil-works/pi-coding-agent` 1.4.0 on npm (still the latest on 1 November 2026) with Node.js 22.19 or newer stated, install scripts for macOS, Linux and Windows, Nix and standalone binaries (20). A public CI workflow builds, checks and tests on every push to main and runs an MCP client conformance job. The run on the commit we cloned (ce950d7, 8 October 2026) passed, but eight of the last 15 runs on main, all on 7 and 8 October, failed. Run results weren't readable on 23 October, so this stands per the 8 October check (15). The repository API reported 308 open issues and pull requests against 113,417 stars on 8 October, not re-read on 23 October. Issues from new contributors are closed automatically and reviewed daily by maintainers, per CONTRIBUTING.md, so the open count understates what is reported, and we couldn't sample reply times (16). A dated changelog with Breaking Changes sections and migration steps, but breaking changes ship outside major versions. The Azure provider rename shipped in patch release 1.0.3 on 5 October 2026, minor release 1.2.0 on 12 October carried four (theme schema location, `before_agent_start`, busy-session behaviour and `pi mcp list --json` output), and 1.3.0 required `/v1` on `kimi-coding` base URL overrides under Changed. The same reading as agent-zero and mistral-vibe-cli, and these breaks also take a deduction under negative events (9). 1.4.0 on 21 October 2026, with 1.0.0 dated 1 October 2026 (15).); 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.)