# Letta vs Orca (slim)

> Letta scores 59.7 (C) to Orca's 57.4 (C) for agent harnesses. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/letta-vs-orca.md (~4,700 tokens) · this version ~1,380 tokens · JSON https://www.anchorterminal.com/compare/letta-vs-orca.json · canonical https://www.anchorterminal.com/compare/letta-vs-orca
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · MCP: https://www.anchorterminal.com/mcp · Updated: 2026-11-07
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Letta scores 59.7 (C) on agent readiness against Orca's 57.4 (C), and leads in 4 of 7 scored categories. Orca leads on security & auth. Both do agent harnesses.

- Letta: C 59.7, rank #684 of 1486 · https://www.anchorterminal.com/tools/letta.min.md
- Orca: C 57.4, rank #791 of 1486 · https://www.anchorterminal.com/tools/orca.min.md
- Letta, good for Long-lived coding agents and assistants that keep memory and identity across sessions and machines. Ahead on Schema & documentation, 70 against 65; Payments & pricing, 60 against 40; Maintenance & community, 85 against 75. Also Runs on your own machine.
- Orca, good for Developers who want an orchestrator agent to split work across parallel coding agents, on desktop or mobile. Ahead on Security & auth, 43 against 35. Also No key needed to call it.

| Category | Letta | Orca |
| --- | --- | --- |
| Reliability (16%) | 58 | 58 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 70 | 65 |
| Agent ergonomics (13%) | 67 | 70 |
| Security & auth (14%) | 35 | 43 |
| Payments & pricing (10%) | 60 | 40 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 85 | 75 |
| Transparency & trust (7%) | 55 | 54 |

| Fact (where they differ) | Letta | Orca |
| --- | --- | --- |
| Vendor | Letta | Lovecast Inc. |
| Transports | stdio |  |
| Auth | OAuth or key | None |
| Pricing | Freemium | Free |
| Licence | Apache-2.0 | MIT |
| llms.txt | yes | no |
| Terms last updated | no date given | no document linked |
| Privacy policy last updated | no date given | no document linked |
| Customer content may train models | not found in the text | not read yet |
| Terms restrict automated access | not found in the text | not read yet |
| Terms restrict benchmarking | not found in the text | not read yet |
| Terms or service can change without notice | not found in the text | not read yet |
| Arbitration or class-action waiver | yes | not read yet |
| Popularity | 3.8k stars, 86k npm/wk, 2.2k PyPI/wk | none |

Why the edge:
- Payments & pricing, Letta +20: Letta 60 (No x402, MPP or L402 (0 of 40). Per-unit API prices are public, $0.10 per active agent a month and $0.00015 a second of tool execution, plus plan prices (20). A $0 plan with bring-your-own keys; no card is mentioned (20). The CLI runs locally without signing in (20). Total 60.); Orca 40 (Scored on the cloud option. No protocol (0). The cloud price wasn't found on the pages read (0). The desktop app is free and MIT with no card (20). The local app needs no sign-up that we found (20). 0 + 0 + 20 + 20 = 40.)
- Maintenance & community, Letta +10: Letta 85 (v0.34.42 on 6 November 2026 (30). Dozens of releases in 90 days (20). Pull requests are merged daily; recent issues from users have few replies (15 of 25). npm and PyPI packages and the Agent SDK track the releases (12 of 15). Lock files, CI and nightly smoke tests (8 of 10). Total 85.); Orca 75 (Tags to v1.4.251 and commits on 6 November 2026 (30). Many releases in 90 days (20). GitHub issues and pull requests weren't read (GitHub's pages refuse these sessions), so that line is scored absent (0). Current builds (15). Extensive CI (10). 30 + 20 + 0 + 15 + 10 = 75.)
- Security & auth, Orca +8: Letta 35 (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 injection posture, 15 for audit and 20 for the security programme. Letta Cloud is the default backend, so agent state and conversations go to Letta's servers, and telemetry is on by default (10 of 30). The default permission mode is `unrestricted`; `standard`, `acceptEdits` and `strict` are opt-in, and cloud sandboxes exist for remote work (4 of 20). No prompt-injection guidance found for fetched pages or channel messages (5 of 15). Conversation search and git history of memory give an operator a record of what the agent saw and changed (10 of 15). SECURITY.md routes reports to support@letta.com and scopes out the retired server; no security.txt, bounty or certification found (6 of 20). Total 35.); Orca 43 (Harness reading. Anonymous usage data with an opt-out, per the README's link to its telemetry docs (15 of 30). Worktrees per agent and a sandboxed Linux build (12 of 20). No prompt-injection guidance (5). No audit log (5). A dependency-security workflow (6 of 20). 15 + 12 + 5 + 5 + 6 = 43.)
- Schema & documentation, Letta +5: Letta 70 (Harness reading. docs.letta.com serves llms.txt and a Markdown version of every page, with an `applies_to` block saying which backend and interface each page covers (10). TypeScript types for the Agent SDK and a documented App Server WebSocket protocol, but no JSON Schema or OpenAPI for the harness (15 of 25). Pages say when to use local or cloud backends, subagents and channels (14 of 20). Permission modes and options are typed in the SDK (12 of 15). Example applications and a remote client reference (11 of 15). Releases most days but no changelog file (8 of 15). Total 70.); Orca 65 (Harness reading. A docs site with CLI orchestration and native chat pages (65).)