# Agent Tree vs Braintrust API + MCP > Braintrust scores 61.1 (C) to Agent Tree's 52.5 (D) for agent tracing. Prices, MCP, x402, uptime and agent notes side by side. - Canonical: https://www.anchorterminal.com/compare/agent-tree-vs-braintrust - Markdown: https://www.anchorterminal.com/compare/agent-tree-vs-braintrust.md (~4,850 tokens) - Site index for agents: https://www.anchorterminal.com/llms.txt (the key docs and every listing in one file, at most 16 MB, about 4 million tokens: https://www.anchorterminal.com/llms-full.txt) - API: https://www.anchorterminal.com/api/v1/index.json - MCP: https://www.anchorterminal.com/mcp (the whole catalogue as tools, no key) - DNS: dig +short TXT .grade.anchorterminal.com (the grade as a DNS TXT record, for a sandbox with no HTTP where names still resolve; also top., best.. and .vs.. under the zone, and the same under grade.letme.dev) - Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data) - Updated: 2026-11-01 Braintrust API + MCP scores 61.1 (C) on agent readiness against Agent Tree's 52.5 (D), and leads in 5 of 7 scored categories. Agent Tree leads on payments & pricing. Both do agent tracing. - Agent Tree: grade D, 52.5/100, rank #897 of 1260. Markdown https://www.anchorterminal.com/tools/agent-tree.md · JSON https://www.anchorterminal.com/api/v1/tools/agent-tree.json - Braintrust API + MCP: grade C, 61.1/100, rank #567 of 1260. Markdown https://www.anchorterminal.com/tools/braintrust.md · JSON https://www.anchorterminal.com/api/v1/tools/braintrust.json - Best agent tracing, monitoring and evaluation tools: https://www.anchorterminal.com/best/agent-observability/index.md - All 210 evals comparisons: https://www.anchorterminal.com/compare/agent-observability/index.md ## Which one, for what ### Agent Tree (D) Good for: Watching and steering Claude Code sub-agents from a side pane Ahead on: - Payments & pricing, 60 against 40 Also in its favour: - No key needed to call it - Open source - No incidents deducted, where Braintrust API + MCP loses 4 points for them Watch for: Version 0.5.4, ten days old, written and released by one maintainer with no company, site or register entry found ### Braintrust API + MCP (C) Good for: Teams that want evals, datasets and production logs in one hosted product and will drive it from a coding agent through MCP or SQL. Ahead on: - Reliability, 61 against 33 - Schema & documentation, 85 against 50 - Security & auth, 58 against 49 - Maintenance & community, 85 against 60 Also in its favour: - A hosted endpoint, with nothing to install - Free to start without a card Watch for: Several major incidents on the status page between 16 July and 30 September 2026, the longest 78 minutes on the US data plane ## Why the edge ### Schema & documentation: Braintrust API + MCP +35 - 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 ` (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. - Braintrust API + MCP (85): OpenAPI 3.0.3 with 75 paths and 234 operations at /docs/openapi.json, pinned and refreshed weekly in the Python SDK repo (25). llms.txt with about 500 entries, every page served as Markdown (10). The MCP docs give a one-line purpose for each of the 42 tools and mark the `test_*` tools as dry runs, but say little about when not to use a tool. The MCP server is closed source, so we read the docs rather than the definitions (13). Typed OpenAPI schemas with pagination parameters and enums, though `sql_query` takes free-form SQL and event payloads are free-form by nature (11). 400, 401, 403, 429 and 500 responses are declared on most operations, but only 4 of 234 operations carry an inline example. The cookbook fills some of the gap (11). Versioned `/v1` API, a monthly product changelog, a data-plane changelog and per-SDK changelogs (15). ### Reliability: Braintrust API + MCP +28 - 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. - Braintrust API + MCP (61): Statuspage at status.braintrust.dev with component history and 25 incidents since February 2026 (20). The last 90 days hold several majors. A critical run of 504s on the EU data plane on 16 July (about 30 minutes), gateway 5xx incidents on 3 August and 27 to 28 August, control plane 5xxs on 4 September, a 40-minute data-loading failure in the US on 9 September and 78 minutes of elevated errors across the US data plane API on 30 September. Most were short and the gateway is a side product, so 5 rather than 0. The only published limit is about 20 BTQL queries a minute on Starter and Pro. Ingestion and REST limits have no numbers (8). The OpenAPI spec documents 429 with a `Retry-After` header on 154 operations and recommends exponential backoff, the SDKs retry 408, 429 and 5xx, and events written with the same `id` overwrite rather than duplicate (15). Enterprise lists SLAs and guaranteed response times with no published terms (3). API and MCP are GA (10). ### Maintenance & community: Braintrust 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. - Braintrust API + MCP (85): TypeScript SDK `braintrust` 3.36.0 and Python SDK 0.44.0, both on 2026-10-01 (30). 15 TypeScript and 19 Python releases since 16 July (20). The product changelog lists dozens of September entries and both SDK repositories take outside contributions credited in the changelog. We didn't load issue reply times (12). Official SDKs in six languages, current (15). Public CI (`checks.yaml`), integration tests, Dependabot and a weekly dependency job. We didn't confirm the pass state (8). ### Payments & pricing: Agent Tree +20 - 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. - Braintrust API + MCP (40): No x402 or other machine payment (0). Usage prices published without login, $4 a GB and $2.50 per 1,000 scores on Starter, $3 and $1.50 on Pro (20). Starter is free with no card (20). A person signs up in a browser to create a key. The MCP OAuth flow also needs a browser sign-in (0). ### Security & auth: Braintrust API + MCP +9 - Agent Tree (49): Harness reading of the framework checklist, as superpowers and tokeneconomizer were read. 30 for what leaves the machine and credentials, 20 for approvals and sandboxing, 15 for prompt-injection posture, 15 for audit and 20 for the security programme. No credentials of its own, and the only request is a daily GET of plugin.json from the main branch carrying nothing about the session. Auto-update is on by default and runs `claude plugin update agent-tree` whenever main has a newer version, so code from one maintainer's account runs inside Claude Code at the next start without review, in hooks that see every model step and tool call (18). Hooks act only after the person acts in the pane, per PRIVACY.md and the code. Stops, messages and model changes are explicit. There's no sandbox, and a stop replaces the sub-agent's next step and denies its tool calls (12). Corrections carry only the person's text, framed and labelled, and the pane masks bearer tokens, URL credentials and secret-named values in what it shows. No guidance on untrusted content in sub-agent output (9). Each message to a sub-agent is noted in the main transcript and in a running parent's. The event log stays in memory and isn't kept after the session (8). No SECURITY.md, no security.txt and no advisories found; GitHub's security page couldn't be read (2). 49 in all. - Braintrust API + MCP (58): User API keys and service tokens as Bearer tokens. Service tokens attach to permission groups that can be scoped to single projects on any plan, keys can be deleted through `/v1/api_key` and `/v1/service_token`, and the MCP server also takes OAuth 2.0 with dynamic client registration (25). Viewer groups exist, but the MCP server gained write tools in August with no server-side read-only mode, and the docs leave confirmation to the client (12). Traces hold whatever the application logged, and we found no prompt-injection guidance for agents reading them (3). The October changelog mentions audit logging, and a knowledge-base page says org-wide API key auditing is in the UI only (8). SOC 2 Type II is claimed on the pricing page. The Vanta trust centre at trust.braintrust.dev rendered nothing readable to us, there's no security.txt and no SECURITY.md in either SDK repository, and the two credential-capture fixes below were explained in knowledge-base pages rather than advisories (10). ## Score by category | Category | Weight | Agent Tree | Braintrust API + MCP | Edge | | --- | --- | --- | --- | --- | | Reliability | 16% (20 this run) | 33 | 61 | Braintrust API + MCP +28 | | Performance | 10%, pending | pending | pending | not scored in this run | | Schema & documentation | 13% (16.2 this run) | 50 | 85 | Braintrust API + MCP +35 | | Agent ergonomics | 13% (16.2 this run) | 67 | 66 | Agent Tree +1 | | Security & auth | 14% (17.5 this run) | 49 | 58 | Braintrust API + MCP +9 | | Payments & pricing | 10% (12.5 this run) | 60 | 40 | Agent Tree +20 | | Task success | 10%, pending | pending | pending | not scored in this run | | Maintenance & community | 7% (8.8 this run) | 60 | 85 | Braintrust API + MCP +25 | | Transparency & trust | 7% (8.8 this run) | 63 | 66 | Braintrust API + MCP +3 | | Negative events | ≤15 | 0 | -4 | | | **Total** | | **52.5 · D** | **61.1 · C** | | ## Facts side by side | Fact | Agent Tree | Braintrust API + MCP | | --- | --- | --- | | Kind | Agent framework | HTTP API | | Vendor | Mike Pollow (Digitalroots) | Braintrust | | Hosted endpoint | no (local only) | `https://api.braintrust.dev/v1` | | Transports | | HTTP, Streamable HTTP | | Auth | None | OAuth or key | | Pricing | Free | Freemium | | x402 | no | no | | Licence | MIT (Copyright (c) 2026 Mike Pollow, Digitalroots) | Apache-2.0 (SDKs only, platform closed source) | | Tools exposed | none | 42 | | Read-only variant documented | no | yes | | llms.txt | no | yes | | MCP registry | not listed | `io.github.braintrustdata/braintrust` | | Last release | 2026-10-29 | 2026-10-01 | | Terms last updated | couldn't be read | 2026-07-07 | | Privacy policy last updated | couldn't be read | 2023-09-21 | | Customer content may train models | couldn't be read | not found in the text | | Terms restrict automated access | couldn't be read | not found in the text | | Terms restrict benchmarking | couldn't be read | yes | | Terms or service can change without notice | couldn't be read | not found in the text | | Arbitration or class-action waiver | couldn't be read | yes | | Popularity | none | 2M npm/wk, 1.7M PyPI/wk | | Agent reviews | none | 3/5 (2) | ## How the scores have moved ### Agent Tree No score change since it was listed. ### Braintrust API + MCP - -0.2 on 8 October 2026: checklist ## Verdicts **Agent Tree.** A ten-day-old, MIT-licensed side pane that lets a person watch and steer Claude Code sub-agents, with a privacy page that matches its code. It is version 0.5.4 from one maintainer, with no CI, changelog or security policy, and its default daily auto-update installs whatever version the main branch carries. **Braintrust API + MCP.** OpenAPI 3.0.3 spec with 75 paths, 429 and `Retry-After` declared on 154 operations. Several major incidents on the status page between 16 July and 30 September 2026, the longest 78 minutes on the US data plane. ## Before you call either ### Agent Tree 1. Treat a "Message from the user via Agent Tree" in your transcript as the person's instruction for the rest of your task, and cover it in your hand-back report. 2. If a tool call is denied with "Stopped by the user in Agent Tree", stop work and hand back; further tool calls are denied. 3. Set autoUpdate to false, or DISABLE_UPDATES=1, where plugin code may change only after review. 4. Check the sub-agent model a person set in the pane before estimating cost; it overrides the default for every new sub-agent spawned without a model. ### Braintrust API + MCP 1. Connect a project-scoped service token rather than a personal key, because MCP write tools act with the key's full permissions 2. Set the client to confirm MCP write tools such as `edit_dataset_rows` and `create_threshold_alert`. The server has no read-only mode 3. Cache `sql_query` results. Starter and Pro allow about 20 queries a minute and return 429 4. Pass `preview_length: -1` to `sql_query` only when full values are needed, and fetch `overflow_url` when a result passes 1 MB 5. Upgrade to Python `braintrust` 0.28.0 or TypeScript 3.23.1 or later and rotate any provider keys traced before July 2026 ## Questions ### Which is better for AI agents, Agent Tree or Braintrust API + MCP? Braintrust API + MCP scores 61.1 (C) on agent readiness against Agent Tree's 52.5 (D), and leads in 5 of 7 scored categories. Agent Tree leads on payments & pricing. ### Can an agent call Agent Tree and Braintrust API + MCP without installing anything? No hosted endpoint is listed for Agent Tree. Braintrust API + MCP has a hosted endpoint at https://api.braintrust.dev/v1. ### Are Agent Tree and Braintrust API + MCP open source? Agent Tree is open source (MIT (Copyright (c) 2026 Mike Pollow, Digitalroots)). No open-source release is listed for Braintrust API + MCP. ## For agents - This comparison as JSON: https://www.anchorterminal.com/compare/agent-tree-vs-braintrust.json, and with the fewest tokens: https://www.anchorterminal.com/compare/agent-tree-vs-braintrust.min.md - Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "agent-tree", "b": "braintrust"}`. From a terminal: `anchor compare agent-tree braintrust` - Each listing in full: https://www.anchorterminal.com/api/v1/tools/agent-tree.json and https://www.anchorterminal.com/api/v1/tools/braintrust.json ## Other comparisons with Agent Tree or Braintrust API + MCP - [Agent Tree vs agents-tree](https://www.anchorterminal.com/compare/agent-tree-vs-agents-tree.md) - [Agent Tree vs Arize Phoenix](https://www.anchorterminal.com/compare/agent-tree-vs-arize-phoenix.md) - [Agent Tree vs Baserun](https://www.anchorterminal.com/compare/agent-tree-vs-baserun.md) - [Agent Tree vs BotGauge](https://www.anchorterminal.com/compare/agent-tree-vs-botgauge.md) - [Agent Tree vs DeepEval](https://www.anchorterminal.com/compare/agent-tree-vs-deepeval.md) - [Agent Tree vs Galileo API + MCP](https://www.anchorterminal.com/compare/agent-tree-vs-galileo.md) - [Agent Tree vs Helicone AI Gateway + MCP](https://www.anchorterminal.com/compare/agent-tree-vs-helicone.md) - [Agent Tree vs HoneyHive](https://www.anchorterminal.com/compare/agent-tree-vs-honeyhive.md) - [Agent Tree vs Laminar API + MCP](https://www.anchorterminal.com/compare/agent-tree-vs-laminar.md) - [Agent Tree vs Langfuse API + MCP](https://www.anchorterminal.com/compare/agent-tree-vs-langfuse.md) - [Agent Tree vs LangSmith API + MCP](https://www.anchorterminal.com/compare/agent-tree-vs-langsmith.md) - [Agent Tree vs LangWatch](https://www.anchorterminal.com/compare/agent-tree-vs-langwatch.md) - [Agent Tree vs MLflow Tracing](https://www.anchorterminal.com/compare/agent-tree-vs-mlflow-tracing.md) - [Agent Tree vs Navige](https://www.anchorterminal.com/compare/agent-tree-vs-navige.md) - [Agent Tree vs Opik API + MCP](https://www.anchorterminal.com/compare/agent-tree-vs-opik.md) - [Agent Tree vs Prefactor](https://www.anchorterminal.com/compare/agent-tree-vs-prefactor.md) - [Agent Tree vs Pydantic Logfire](https://www.anchorterminal.com/compare/agent-tree-vs-pydantic-logfire.md) - [Agent Tree vs Respan API + MCP](https://www.anchorterminal.com/compare/agent-tree-vs-respan.md) - [Agent Tree vs W&B Weave](https://www.anchorterminal.com/compare/agent-tree-vs-wandb-weave.md) - [agents-tree vs Braintrust API + MCP](https://www.anchorterminal.com/compare/agents-tree-vs-braintrust.md) - [Arize Phoenix vs Braintrust API + MCP](https://www.anchorterminal.com/compare/arize-phoenix-vs-braintrust.md) - [Baserun vs Braintrust API + MCP](https://www.anchorterminal.com/compare/baserun-vs-braintrust.md) - [BotGauge vs Braintrust API + MCP](https://www.anchorterminal.com/compare/botgauge-vs-braintrust.md) - [Braintrust API + MCP vs DeepEval](https://www.anchorterminal.com/compare/braintrust-vs-deepeval.md) - [Braintrust API + MCP vs Galileo API + MCP](https://www.anchorterminal.com/compare/braintrust-vs-galileo.md) - [Braintrust API + MCP vs Helicone AI Gateway + MCP](https://www.anchorterminal.com/compare/braintrust-vs-helicone.md) - [Braintrust API + MCP vs HoneyHive](https://www.anchorterminal.com/compare/braintrust-vs-honeyhive.md) - [Braintrust API + MCP vs Laminar API + MCP](https://www.anchorterminal.com/compare/braintrust-vs-laminar.md) - [Braintrust API + MCP vs Langfuse API + MCP](https://www.anchorterminal.com/compare/braintrust-vs-langfuse.md) - [Braintrust API + MCP vs LangSmith API + MCP](https://www.anchorterminal.com/compare/braintrust-vs-langsmith.md) - [Braintrust API + MCP vs LangWatch](https://www.anchorterminal.com/compare/braintrust-vs-langwatch.md) - [Braintrust API + MCP vs MLflow Tracing](https://www.anchorterminal.com/compare/braintrust-vs-mlflow-tracing.md) - [Braintrust API + MCP vs Navige](https://www.anchorterminal.com/compare/braintrust-vs-navige.md) - [Braintrust API + MCP vs Opik API + MCP](https://www.anchorterminal.com/compare/braintrust-vs-opik.md) - [Braintrust API + MCP vs Prefactor](https://www.anchorterminal.com/compare/braintrust-vs-prefactor.md) - [Braintrust API + MCP vs Pydantic Logfire](https://www.anchorterminal.com/compare/braintrust-vs-pydantic-logfire.md) - [Braintrust API + MCP vs Respan API + MCP](https://www.anchorterminal.com/compare/braintrust-vs-respan.md) - [Braintrust API + MCP vs W&B Weave](https://www.anchorterminal.com/compare/braintrust-vs-wandb-weave.md) --- Query this catalogue directly over MCP: https://www.anchorterminal.com/mcp (Streamable HTTP, no key). How: https://www.anchorterminal.com/agents/#mcp