Letta vs Paperclip

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.

Paperclip 64

Harness reading of the framework checklist, as used 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. Anonymous usage telemetry is on by default and goes to telemetry.paperclip.ing. The README lists what is excluded and four opt-outs, and Sentry and OpenTelemetry stay off until configured. We found no first-run notice in the CLI source (18). Board approvals for hires and strategy, execution policies and per-action connection permissions, but claude_local defaults dangerouslySkipPermissions to true, codex_local defaults to bypassing approvals and the sandbox, local agents run on the host, sandbox providers are optional plugins and the default local_trusted mode has no login (10). A documented low_trust_review preset contains agents that read untrusted pull requests or tickets. It is opt-in (10). An activity log of mutating actions, run logs, cost events and audited board API keys (14). SECURITY.md with GitHub private reporting and twelve advisories published per the 8 October check, three now with CVEs in OSV. No security.txt, bug bounty or SOC 2 report found (12).

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.

Paperclip 81

The running server publishes OpenAPI at /api/openapi.json and validates requests with Zod, and the MCP server's tools take Zod schemas. No copy of the spec is published on the docs site, and paperclip.ing/openapi.json describes only the website (22). llms.txt at paperclip.ing, and docs pages answer as Markdown at .md (10). An API reference page per resource and task guides, but the MCP tool descriptions are one line each, such as List agents in a company (13). Typed inputs throughout, apart from the paperclipApiRequest tool, which takes any path under /api and a JSON body (12). cURL, JavaScript and Python examples and a status-code table, with one {error} shape and an occasional details field (12). A changelog page for every stable release and release notes in the repository, but the API path carries no version (12).

Letta 55

Apache-2.0 (30). The privacy policy has no date, no legal entity and no retention periods, and says hosted message data may train future models (8 of 30). The README and docs mark AgentFile, the Electron app and the V1 server as deprecated or retired, without dated notice periods (12 of 20). Telemetry is described in the privacy policy only as basic and opt-out when supported; the LETTA_CODE_TELEM=0 switch appears only in the source (5 of 20). Total 55.

Paperclip 66

MIT (30). The privacy policy of 23 July 2026 separates self-hosted use from the hosted services and names Paperclip Labs, Inc., but keeps data as long as reasonably necessary, lists no subprocessors, and the 90-day telemetry retention appears only in source. The terms grant a broad licence over content sent to the services and allow model training on opt-in detailed telemetry (16). Release notes carry dated Breaking Changes sections and upgrade guides, with no written deprecation policy or notice period (10). The README discloses telemetry, what it excludes and four opt-outs, and the event contract is public in the repository, but it is on by default (17).

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.

Paperclip 78

Version 2026.1023.0, released on 23 October 2026 per its notes and the site banner (30). Ten stable releases from 2026.817.0 (17 August) to 2026.1023.0 in the 90 days to 4 November (20). Per the 8 October check, not re-read on 4 November, 650 pull requests merged in the last 30 days, but 2,849 issues and 3,338 pull requests were open, 1,396 open issues had no comment, and 309 of the 472 still-open issues from the two weeks before had none (8). paperclipai and @paperclipai/mcp-server publish from the same release workflow. We did not check the MCP registry (12). CI on master, a lockfile refresh workflow and signed image attestations (8). 30 + 20 + 8 + 12 + 8 = 78.