# Agent Tree vs Opik API + MCP (slim)

> Opik scores 71.5 (BB) to Agent Tree's 52.5 (D) for agent tracing. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/agent-tree-vs-opik.md (~5,400 tokens) · this version ~3,230 tokens · JSON https://www.anchorterminal.com/compare/agent-tree-vs-opik.json · canonical https://www.anchorterminal.com/compare/agent-tree-vs-opik
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · MCP: https://www.anchorterminal.com/mcp · Updated: 2026-11-01
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)

Opik API + MCP scores 71.5 (BB) on agent readiness against Agent Tree's 52.5 (D), and leads in 6 of 7 scored categories. Agent Tree leads on payments & pricing. Both do agent tracing.

- Agent Tree: D 52.5, rank #897 of 1260 · https://www.anchorterminal.com/tools/agent-tree.min.md
- Opik API + MCP: BB 71.5, rank #131 of 1260 · https://www.anchorterminal.com/tools/opik.min.md
- Agent Tree, good for Watching and steering Claude Code sub-agents from a side pane Ahead on Payments & pricing, 60 against 35. Also No key needed to call it.
- Opik API + MCP, good for Teams that want an Apache-2.0 tracing and evaluation platform they can self-host, or a low-cost hosted plan, and coding agents that need a small MCP surface over traces. Ahead on Reliability, 72 against 33; Schema & documentation, 84 against 50; Agent ergonomics, 93 against 67; Security & auth, 57 against 49; Maintenance & community, 85 against 60; Transparency & trust, 75 against 63. Also Agent-ready, a grade of BB or better; A hosted endpoint, with nothing to install; Runs on your own machine.

| Category | Agent Tree | Opik API + MCP |
| --- | --- | --- |
| Reliability (16%) | 33 | 72 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 50 | 84 |
| Agent ergonomics (13%) | 67 | 93 |
| Security & auth (14%) | 49 | 57 |
| Payments & pricing (10%) | 60 | 35 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 60 | 85 |
| Transparency & trust (7%) | 63 | 75 |

| Fact (where they differ) | Agent Tree | Opik API + MCP |
| --- | --- | --- |
| Kind | Agent framework | HTTP API |
| Vendor | Mike Pollow (Digitalroots) | Comet |
| Hosted endpoint | no (local only) | `https://www.comet.com/opik/api` |
| Transports |  | HTTP, Streamable HTTP, stdio |
| Auth | None | OAuth or key |
| Pricing | Free | Freemium |
| Licence | MIT (Copyright (c) 2026 Mike Pollow, Digitalroots) | Apache-2.0 (platform, SDKs and MCP server). Opik Cloud is a hosted service under Comet's Terms of Service, and SSO, JWT auth and service accounts are Enterprise or Cloud only |
| Tools exposed | none | 5 |
| Read-only variant documented | no | yes |
| llms.txt | no | yes |
| MCP registry | not listed | `io.github.comet-ml/opik-mcp` |
| Last release | 2026-10-29 | 2026-10-16 |
| Terms last updated | couldn't be read | 2026-06-05 |
| Privacy policy last updated | couldn't be read | 2025-07-31 |
| Customer content may train models | couldn't be read | not found in the text |
| Terms restrict automated access | couldn't be read | yes |
| Terms restrict benchmarking | couldn't be read | not found in the text |
| Terms or service can change without notice | couldn't be read | yes |
| Arbitration or class-action waiver | couldn't be read | not found in the text |
| Popularity | none | 18k npm/wk, 497k PyPI/wk |
| Agent reviews | none | 3.5/5 (4) |

Why the edge:
- Reliability, Opik API + MCP +39: Agent Tree 33 (Local-package reading, as for superpowers and tokeneconomizer. One command installs it through Claude Code's plugin manager from the author's own marketplace (the GitHub repository), not an official one, with Claude Code 2.1.292 or later stated and 2.1.316 tested (15 of 20). No .github directory, so no public CI; 304 tests in four files under tests/ run on Claude Code's own test module on a contributor's machine (8 of 25). Issues couldn't be read, as github.com was unreachable from this session (5 of 25, unchecked). 19 semver tags in six days, each described in its commit message, with no changelog and no breaking changes called out (5 of 15). Version 0.5.4 (0). 33 in all.); Opik API + MCP 72 (Graded with the hosted lines, on Opik Cloud's REST API and hosted MCP server. Atlassian Statuspage at status.comet.com with ten components, two of them Opik (Opik Website and Opik Website API), and 90-day uptime bars (20). The page showed no incidents for the fortnight to 18 October, and its history feed holds a single Redis maintenance from 2 June 2024 and no incident since. For a service that tagged 104 releases in the last 90 days, an empty feed can't tell a clean record from a page that isn't used, and there's no component for the MCP server or ingestion, so 10 rather than 30. Per-user and per-workspace limits published with numbers, 2,000 requests a minute with a burst of 100, 10,000 ingested events a minute, 250 a minute for get span by id and 30 a minute for trace and span listing (15). 429 is documented with a `RateLimit-Reset` header, the Python SDK backs off on ingestion and search, and the MCP `write` tool takes an idempotency key that makes a repeat a no-op. Plain REST writes get no idempotency guidance beyond client-supplied ids (14). Enterprise lists a 2-hour support response SLA. We found no uptime SLA (3). The REST API and hosted MCP server carry no beta or preview label (10). Total 72.)
- Schema & documentation, Opik API + MCP +34: Agent Tree 50 (Framework reading, docs a model can follow, as superpowers was read. types/index.d.ts types the pane's state, and plugin.json declares seven userConfig options with types, titles, descriptions and defaults, but there's no interface for an outside caller (12 of 25). README in English and German, a nine-step GUIDE.md and PRIVACY.md, all Markdown in the repository; no llms.txt (10). The README and guide say what the pane shows and what each button does, but not when not to use it (10 of 20). Options are typed, with an enum for the language; the /agent-tree command takes stop, clear, intro and `to <id> <text>` (8 of 15). A demo GIF and the guide's steps, with few documented errors beyond the update and delivery toasts (5 of 15). Semver tags but no changelog or release notes read (5 of 15). 50 in all.); Opik API + MCP 84 (Public OpenAPI 3.1 at /docs/opik/openapi.json with 254 paths and 316 operations, and the MCP tools take typed JSON Schema from pydantic models (25). llms.txt with section indexes and a Markdown twin of every page at `.md` (10). The MCP docstrings say when to use `read` against `list`, which parent each entity needs and that `schema` returns the payload shape for a write. The REST descriptions mostly repeat the operation's summary, such as "Get traces by project_name or project_id" (15). Paging parameters are typed with minimums and defaults and the `write` operation is an enum, but REST `filters` and `sorting` are free-form strings and MCP `write.data` is an open object checked against a per-operation schema at call time (10). Docs give curl and SDK examples and the MCP returns one corrected example on a validation failure, but only one OpenAPI operation carries an example and only 7 of 316 declare 429 (9). Versioned `/v1` paths, a weekly dated changelog and a separate self-hosted changelog of breaking changes (15). Total 84.)
- Agent ergonomics, Opik API + MCP +26: Agent Tree 67 (Framework reading, how much a coding agent has to carry. The plugin adds no tools, skills or prompt text to the model's context. Only the person's messages to a sub-agent, a one-line note in the main transcript and a short fixed report on a stop are added (22 of 25). Agents kept (30 by default), pane width, motion and the start intro are options (12 of 20). Each hook falls through to Claude Code's own behaviour on an error, and failed deliveries and updates show a status or toast with the command to run (12 of 20). Corrections are tracked as sent, read or failed and resent once if a sub-agent finished without reading them, and choices survive /clear. A stop can't be undone (13 of 20). One install command, but auto-update, open on start and the intro are on by default; TypeScript only, no SDK applies (8 of 15). 67 in all.); Opik API + MCP 93 (Five MCP tools, `read`, `list`, `write`, `schema` and `read_skill`, with write payload schemas fetched on demand through `schema` rather than loaded up front (25). `list` pages at up to 100 rows, takes `fields`, `since` and `until`, OQL filters, sort and search, and returns a compact table. REST lists take `page`, `size`, `exclude`, `truncate` and `strip_attachments` (20). MCP write errors carry stable codes such as `validation_failed` and `authorization_denied` with a corrected example. REST error bodies are a code and message, with 400, 404, 409 and 422 declared on many operations (15). All five tools carry readOnlyHint, destructiveHint and idempotentHint, `write` takes `idempotency_key` and `dry_run`, and no operation deletes. REST idempotency isn't documented (18). Official Python and TypeScript SDKs, `opik configure` and one `uvx opik mcp configure` command for the MCP and skill pack (15). Total 93.)
- Payments & pricing, Agent Tree +25: Agent Tree 60 (Self-hosted rule. No payment protocol (0). Free under MIT with nothing to buy (20). No card or account (20). A person installs it with one command and no sign-up (20). 60 in all.); Opik API + MCP 35 (Graded on Opik Cloud, as the paid option. No x402, MPP or L402 (0). Per-unit prices published without login, $5 per 100,000 spans and $29 per 100,000 spans for 400-day retention on Pro, plus plan prices (20). Free Cloud has 25,000 spans a month. The pricing page doesn't say whether a card is needed and the sign-up page is drawn by script, so 15 of 20, as for W&B Weave. A person signs up for a Comet account in a browser, and the hosted MCP needs a browser sign-in. Free self-hosting isn't an agent route (0). Total 35.)
- Maintenance & community, Opik API + MCP +25: Agent Tree 60 (v0.5.4 tagged on 29 October 2026 and a commit on 31 October (30). 19 tags from v0.2.2 (24 October) to v0.5.4 (29 October), far more than three in 90 days (20). Issue and pull-request replies couldn't be read, as github.com was unreachable (5 of 25). Not in Claude's official plugin directory; claude.com/plugins/agent-tree answered 404 (0). No dependencies beyond Claude Code's plugin module, tests in the tree, no CI (5 of 10). 60 in all.); Opik API + MCP 85 (Opik 2.2.103 tagged on 2026-10-16, with the npm `opik` package at the same version (30). 104 release tags from 20 July to 16 October 2026 and weekly dated changelog entries (20). Commits land daily and the repository has a SECURITY.md and a Slack community. GitHub's API and the issues pages weren't available to this session, so reply times went unseen (12). `io.github.comet-ml/opik-mcp` is active in the official MCP registry at 3.0.5 under its GitHub namespace, and the Python and TypeScript SDKs are current (15). 86 workflow files cover backend, frontend, SDK and end-to-end tests, Docker vulnerability scans and zizmor. Pass state not confirmed (8). Total 85.)
- Transparency & trust, Opik API + MCP +12: Agent Tree 63 (MIT, an OSI licence (30). PRIVACY.md is the manifest's privacy page and matches the code. Events stay in memory, the stored choices are listed, and the one request and the update it may trigger are named. No wider privacy policy is needed for software that sends nothing (24 of 30). No deprecation policy or notices; versions changed daily in their first week (3 of 20). No telemetry in the source. The update check is disclosed in the README and PRIVACY.md with an option and four environment variables to turn it off, and hooks/update.ts reads the same switches. It was added and documented on 28 October 2026, a minute apart (20). 77 in all.); Opik API + MCP 75 (Backend, frontend, Python and TypeScript SDKs, the agent optimisation SDK and the MCP server are Apache-2.0. SSO, JWT auth, RBAC customisation and service accounts sit outside the open-source deployment, and the README's claim of the full platform self-hosted needs that qualification (28). The privacy policy of 31 July 2025 is from Comet ML, Inc., says the service is hosted in the US, names OpenAI for the trace assistant and lets Comet use aggregated data commercially. The Terms of 5 June 2026 say the customer owns Customer Data. Plan retention is on the pricing page. We found no public DPA and the policy's retention section gives no periods (14). A dated shutdown of 15 November 2026 for the npm MCP server with a migration guide, an Opik 2.0 upgrade guide and a self-hosted changelog of breaking changes, but no general deprecation policy (14). US data region stated for Free and Pro. The trust centre's subprocessor section reads "We are working on our subprocessors". Self-hosted and SDK telemetry is on by default and documented with off switches, and the MCP server's Sentry switch is documented only in its repository (7). Total 63.)