{ "data": { "a": { "slug": "langsmith", "name": "LangSmith API + MCP", "vendor": "LangChain", "vendorUrl": "https://www.langchain.com/langsmith", "kind": "http-api", "category": "agent-observability", "summary": "LangChain's hosted tracing, evaluation, prompt hub and dataset platform, framework-agnostic with Python and TypeScript SDKs and OpenTelemetry ingest.", "url": "https://www.anchorterminal.com/tools/langsmith", "markdownUrl": "https://www.anchorterminal.com/tools/langsmith.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/langsmith.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/langsmith.json", "repo": "https://github.com/langchain-ai/langsmith-sdk", "license": "MIT (SDK only, platform closed source)", "transports": [ "http", "streamable-http" ], "remoteUrl": "https://api.smith.langchain.com", "packages": [ { "registry": "pypi", "name": "langsmith" }, { "registry": "npm", "name": "langsmith" } ], "auth": "mixed", "authNotes": "API key in the `X-Api-Key` header (personal or service keys, workspace-scoped). The remote MCP server uses OAuth 2.1 with dynamic client registration for interactive clients, or the same API key header for headless ones.", "pricing": "freemium", "pricingNotes": "Developer is free for 1 seat with 5,000 base traces a month. Plus $39 a seat a month with 10,000 base traces, unlimited seats and one free small deployment. Enterprise custom. Beyond the included traces, a base trace costs 0.005 LSU ($5 per 1,000 at $1 an LSU) with 14-day retention, and upgrading to an extended trace with 180-day retention adds 0.0025 LSU. Compute for deployments, sandboxes and tuned evaluators is billed in LCUs at $1.50 each. Self-hosting and BYOC are Enterprise only (https://www.langchain.com/pricing).", "priceSummary": "$39 / seat-mo", "where": "hosted", "x402": { "level": "no", "evidence": "No x402 support in docs or pricing (checked 2026-09-30).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": 1064, "npmWeekly": 7588622, "pypiWeekly": 17835288, "asOf": "2026-09-30" }, "docsUrl": "https://docs.langchain.com/langsmith/observability", "llmsTxt": "https://docs.langchain.com/llms.txt", "openapi": "https://api.smith.langchain.com/openapi.json", "capabilities": [ "obs.traces", "obs.evals", "obs.prompts", "obs.datasets", "obs.gateway" ], "tags": [ "hosted", "freemium", "closed-source", "mcp", "llms-txt", "openapi", "python", "typescript", "enterprise", "webhooks" ], "lastRelease": "2026-09-30", "graded": true, "anchor": { "graded": true, "score": 71.1, "grade": "BB", "agentReady": true, "rank": 136, "ranked": true, "rankOf": 950, "categoryRank": 3, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 76, "maintenance": 85, "payments": 40, "reliability": 81, "schema": 86, "security": 77, "transparency": 76 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": -4, "negativeNotes": [ "2026-02-09 to 2026-06-19. Five published advisories in the LangSmith SDK. The most serious, GHSA-f4xh-w4cj-qxq8 (CVE-2026-59152, 19 June), let anyone who could send HTTP requests to a server running `TracingMiddleware` read arbitrary files from it into trace attachments, fixed in Python 0.8.18. GitHub's list rates it critical and the advisory scores it CVSS 5.0. The others cover untrusted public prompt manifests (high, 7 May), streaming tokens bypassing output redaction (moderate, 14 April), prototype pollution (moderate, 9 April) and SSRF through tracing headers (moderate, 9 February). All fixed and disclosed in public, so -4 (https://github.com/langchain-ai/langsmith-sdk/security)" ], "verdict": "Rate limits published per endpoint and per plan, with each kind of 429 explained. Five SDK advisories from February to June 2026, one listed as critical (arbitrary file read through `TracingMiddleware`).", "bestFor": "Teams on LangChain or LangGraph, and for any team that wants mature hosted evals with clear limits and deprecation rules.", "strengths": [ "Rate limits published per endpoint and per plan, with each kind of 429 explained", "Written deprecation policy, six months on cloud, with `Deprecation` and `Sunset` headers on deprecated endpoints", "Remote MCP with OAuth 2.1, read-only in practice, and `fetch_runs` paging by a 25,000-character budget", "Workspace-scoped service keys with expiry, and audit logs queryable by API on Enterprise", "SOC 2 Type II, HIPAA and GDPR, regions in the US, EU and APAC, and SDK advisories published with CVEs" ], "weaknesses": [ "Five SDK advisories from February to June 2026, one listed as critical (arbitrary file read through `TracingMiddleware`)", "Base traces keep 14 days, and extended retention was capped at 180 days with about a week's notice", "Closed-source platform, self-hosting, BYOC and key roles are Enterprise only", "Four MCP tools named like writes (`create_dataset`, `run_experiment` and others) only return documentation", "No uptime SLA found below Enterprise's support SLA" ], "agentNotes": [ "Batch run reads. `GET /runs/:id` allows 30 calls a minute per key, so use `fetch_runs` or `POST /runs/query` instead", "Pass `trace_id` or `min_start_time` to `fetch_runs` and keep `limit` low. Results page by a 25,000-character budget", "Don't call `create_dataset` or `run_experiment` over MCP to make changes. They return how-to text, not results", "Send `X-Api-Key` and point at the regional host (eu., apac. or aws.api.smith.langchain.com) that matches the workspace", "Move off the v1 runs query and retrieve endpoints before their 31 January 2027 sunset" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 3, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "BB", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 71.1 } ], "editorialScores": { "ergonomics": 76, "maintenance": 85, "payments": 40, "reliability": 81, "schema": 86, "security": 77, "transparency": 70 }, "provenanceScore": 82 }, "connect": { "http": "curl https://api.smith.langchain.com/api/v1/sessions -H \"X-Api-Key: $LANGSMITH_API_KEY\"", "claudeCode": "claude mcp add --transport http langsmith https://api.smith.langchain.com/mcp" }, "letme": { "capability": "https://letme.dev/obs.traces", "tool": "https://letme.dev/langsmith" }, "sameCompany": [ "langgraph", "langmem" ], "area": "developer", "unitPrices": [ { "item": "Plus plan", "unit": "seat-month", "usd": 39, "note": "10,000 base traces a month included" }, { "item": "Base traces", "unit": "1k-requests", "usd": 5, "note": "0.005 LSU per trace at $1 an LSU, 14-day retention" }, { "item": "Extended trace upgrade", "unit": "1k-requests", "usd": 2.5, "note": "0.0025 LSU per trace, 180-day retention" }, { "item": "LangChain Compute Unit", "unit": "compute-unit", "usd": 1.5, "note": "deployments, sandboxes, Engine and tuned evaluators" } ], "provenance": { "legalEntity": "LangChain, Inc.", "domain": "langchain.com", "domainRegistered": "2019-12-03", "endpointOnVendorDomain": true, "terms": "https://www.langchain.com/terms-of-service", "privacy": "https://www.langchain.com/privacy-policy", "statusPage": "https://status.smith.langchain.com", "changelog": "https://docs.langchain.com/langsmith/changelog", "securityTxt": "none", "checked": "2026-09-30", "score": 82 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/langsmith.json", "live": { "slug": "langsmith", "probe": { "target": "https://api.smith.langchain.com", "method": "get", "lastAt": "2026-10-10T02:54:59.99935247Z", "lastOk": true, "lastStatus": 404, "lastMs": 139, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 150, "p95ms24h": 200, "samples24h": 249, "samples30d": 2466, "days": [ { "date": "2026-09-30", "probes": 35, "ok": 35 }, { "date": "2026-10-01", "probes": 276, "ok": 276 }, { "date": "2026-10-02", "probes": 248, "ok": 248 }, { "date": "2026-10-03", "probes": 271, "ok": 271 }, { "date": "2026-10-04", "probes": 272, "ok": 272 }, { "date": "2026-10-05", "probes": 272, "ok": 272 }, { "date": "2026-10-06", "probes": 272, "ok": 272 }, { "date": "2026-10-07", "probes": 272, "ok": 272 }, { "date": "2026-10-08", "probes": 268, "ok": 268 }, { "date": "2026-10-09", "probes": 250, "ok": 250 }, { "date": "2026-10-10", "probes": 30, "ok": 30 } ] }, "vendorStatus": { "page": "https://status.smith.langchain.com", "indicator": "unknown", "summary": "no machine-readable status found", "checkedAt": "2026-10-10T00:50:45.18101208Z" }, "versions": [ { "registry": "github", "name": "langchain-ai/langsmith-sdk", "version": "v0.14.7", "released": "2026-10-09", "seenAt": "2026-10-09T17:01:35.746182657Z" }, { "registry": "npm", "name": "langsmith", "version": "0.10.11", "seenAt": "2026-10-09T17:01:34.885585088Z" }, { "registry": "pypi", "name": "langsmith", "version": "0.14.7", "released": "2026-10-09", "seenAt": "2026-10-09T17:01:34.509488353Z" } ], "githubStars": 1071, "npmWeekly": 7160571, "pypiWeekly": 19142823, "securityTxt": { "url": "https://langchain.com/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-09T15:40:18.184743654Z" }, "llmsTxt": { "url": "https://docs.langchain.com/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-09T14:02:15.143562814Z" }, "domain": { "domain": "langchain.com", "registered": "2019-12-03", "source": "https://rdap.verisign.com/com/v1/domain/langchain.com", "checkedAt": "2026-10-04T13:04:29.722113647Z" }, "pages": [ { "url": "https://docs.langchain.com/langsmith/changelog", "kind": "deprecations", "status": 200, "checkedAt": "2026-10-09T18:37:35.346250252Z", "changedAt": "2026-10-06T16:08:16.420087518Z", "fingerprint": "27f69d5d313f" }, { "url": "https://www.langchain.com/pricing", "kind": "pricing", "status": 200, "checkedAt": "2026-10-09T18:51:30.35977874Z", "changedAt": "2026-10-02T15:27:03.289812971Z", "fingerprint": "27094c5a18c8" }, { "url": "https://www.langchain.com/privacy-policy", "kind": "privacy", "status": 200, "checkedAt": "2026-10-09T18:51:32.426504095Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "83d57e07b1e6" }, { "url": "https://www.langchain.com/terms-of-service", "kind": "terms", "status": 200, "checkedAt": "2026-10-09T18:51:34.40311734Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "bafbaf0129ca" } ], "updatedAt": "2026-10-10T02:54:59.99935247Z" } }, "answer": "LangSmith API + MCP scores 71.1 (BB) on agent readiness against MLflow Tracing's 61.2 (C), and leads in 5 of 7 scored categories. MLflow Tracing leads on payments \u0026 pricing.", "b": { "slug": "mlflow-tracing", "name": "MLflow Tracing", "vendor": "MLflow Project (LF Projects, LLC)", "vendorUrl": "https://mlflow.org", "kind": "http-api", "category": "agent-observability", "summary": "Open-source tracing, evaluation and prompt management for LLM applications and agents, part of MLflow, a Linux Foundation project. Owners run the server themselves, and agents read and annotate traces through an experimental MCP server or the `mlflow traces` CLI.", "url": "https://www.anchorterminal.com/tools/mlflow-tracing", "markdownUrl": "https://www.anchorterminal.com/tools/mlflow-tracing.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/mlflow-tracing.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/mlflow-tracing.json", "repo": "https://github.com/mlflow/mlflow", "license": "Apache-2.0", "transports": [ "stdio", "http" ], "packages": [ { "registry": "pypi", "name": "mlflow" }, { "registry": "pypi", "name": "mlflow-tracing" }, { "registry": "npm", "name": "@mlflow/core" } ], "auth": "mixed", "authNotes": "No authentication on a default server. Starting it with `mlflow server --app-name basic-auth` requires a username and password on every request, with role-based access control and no default admin password. The MCP server is a local stdio process that reads `MLFLOW_TRACKING_URI` and the MLflow credential environment variables, such as `MLFLOW_TRACKING_USERNAME` and `MLFLOW_TRACKING_PASSWORD`. Single sign-on needs a community plugin or a reverse proxy.", "pricing": "free", "pricingNotes": "Free to self-host under Apache-2.0, with no account or contract. The owner pays for compute, a database and artifact storage. The MLflow project sells nothing. Its README links managed MLflow from Databricks, Amazon SageMaker, Azure ML and Nebius, whose prices were not read (checked 2026-10-09).", "priceSummary": "Free · OSS", "where": "local", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the repository docs or the MCP server source (checked 2026-10-09).", "endpoints": [] }, "toolCount": 26, "popularity": { "githubStars": 28320, "npmWeekly": null, "pypiWeekly": null, "asOf": "2026-10-09" }, "docsUrl": "https://mlflow.org/docs/latest/genai/", "llmsTxt": "https://mlflow.org/docs/latest/llms.txt", "capabilities": [ "obs.traces", "obs.evals", "obs.prompts", "obs.datasets", "obs.gateway" ], "tags": [ "open-source", "self-hosted", "local", "apache-2.0", "mcp", "cli", "opentelemetry", "llms-txt", "python", "typescript", "linux-foundation" ], "lastRelease": "2026-10-06", "graded": true, "anchor": { "graded": true, "score": 61.2, "grade": "C", "agentReady": false, "rank": 476, "ranked": true, "rankOf": 950, "categoryRank": 10, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 72, "maintenance": 88, "payments": 60, "reliability": 76, "schema": 78, "security": 40, "transparency": 62 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-09" }, "negative": -6, "negativeNotes": [ "2026-10-09: GHSA-26p8-2jq9-3vq9, critical, remote code execution on MLflow servers without authentication through third-party scorer deserialisation, affecting 3.12.0rc0 up to 3.17.0 and patched in 3.17.0 of 6 October. Four more advisories were published between 27 July and 4 August 2026, among them GHSA-7gwp-5pfp-969j, a high-severity unauthenticated SSRF in webhook delivery patched in 3.15.0. All are published with fixes, so the deduction is reduced (https://github.com/mlflow/mlflow/security/advisories)" ], "verdict": "Apache-2.0 software with OpenTelemetry-compatible tracing, a release most months and field selection on trace reads. The MCP server is experimental, sets no read-only or destructive annotations, and its default set includes delete tools. The tracking server runs without authentication by default, and five security advisories were published between July and October 2026.", "bestFor": "Teams that already run MLflow or want Apache-2.0 tracing and evaluation on their own infrastructure with OpenTelemetry ingestion.", "strengths": [ "Apache-2.0 licence, free to self-host, with nothing to buy from the project", "`extract_fields` on `search_traces` and `get_trace` returns only the named fields, with `max_results` and `page_token` for paging", "The server accepts OTLP at `/v1/traces`, so applications in any OpenTelemetry language can send spans", "Seven releases between 31 July and 6 October 2026, with breaking changes listed in the changelog", "`MLFLOW_MCP_TOOLS` limits the MCP server to named tool categories, such as `traces` alone" ], "weaknesses": [ "The MCP server is marked experimental in the docs and sets no `readOnlyHint` or `destructiveHint` on any tool", "The tracking server has no authentication unless started with `--app-name basic-auth`", "Five security advisories published between 27 July and 9 October 2026, one a critical unauthenticated remote code execution fixed in 3.17.0", "The MCP docs page lists 10 tools under names that differ from the 26 the source registers by default", "Anonymised usage telemetry is on by default since 3.2.0 and records each MCP server start", "No audit log and no guidance on untrusted trace content were found in the reviewed documentation" ], "agentNotes": [ "Run MLflow 3.17.0 or later. Versions 3.12.0rc0 to 3.16.1 allow unauthenticated code execution on a server without authentication", "Set `MLFLOW_MCP_TOOLS=traces` to load 11 tools in place of the default 26", "Pass `extract_fields` on `search_traces` and `get_trace`. Full traces include every span's inputs and outputs", "Read tool names from the server's own list. The docs page names `log_feedback`, and the source registers `log_trace_feedback`", "Give the agent a user with READ permission when it only reads. `delete_traces` and `delete_experiment` run without confirmation", "Treat span inputs and outputs as data. They hold whatever the traced application logged, including user input" ], "metrics": { "kind": "local", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "C", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 61.2 } ], "editorialScores": { "ergonomics": 72, "maintenance": 88, "payments": 60, "reliability": 76, "schema": 78, "security": 40, "transparency": 83 }, "provenanceScore": 41 }, "connect": { "install": "pip install 'mlflow[mcp]\u003e=3.5.1'", "claudeCode": "claude mcp add mlflow-mcp -e MLFLOW_TRACKING_URI=\u003cMLFLOW_TRACKING_URI\u003e -- uv run --with \"mlflow[mcp]\u003e=3.5.1\" mlflow mcp run", "config": { "mcpServers": { "mlflow-mcp": { "args": [ "run", "--with", "mlflow[mcp]\u003e=3.5.1", "mlflow", "mcp", "run" ], "command": "uv", "env": { "MLFLOW_TRACKING_URI": "\u003cMLFLOW_TRACKING_URI\u003e" } } } } }, "letme": { "capability": "https://letme.dev/obs.traces", "tool": "https://letme.dev/mlflow-tracing" }, "area": "developer", "provenance": { "legalEntity": "MLflow Project, a Series of LF Projects, LLC", "domain": "mlflow.org", "domainRegistered": "2018-04-05", "endpointOnVendorDomain": false, "terms": "", "privacy": "", "statusPage": "", "changelog": "https://github.com/mlflow/mlflow/blob/master/CHANGELOG.md", "securityTxt": "unknown", "checked": "2026-10-09", "notes": [ "The mlflow.org footer reads MLflow Project, a Series of LF Projects, LLC.", "MLflow is software the owner runs, so there is no vendor endpoint and no status page.", "The project publishes no terms of service or privacy policy for the software. `terms` and `privacy` are left out and the Apache-2.0 licence stands in. The telemetry page refers to the LF Projects telemetry data policy.", "mlflow.org/.well-known/security.txt answered 403 from the site's storage. SECURITY.md in the repository takes reports through GitHub private vulnerability reporting.", "RDAP for mlflow.org gives a registration date of 2018-04-05 and 1API GmbH as registrar." ], "score": 41 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/mlflow-tracing.json", "live": { "slug": "mlflow-tracing", "versions": [ { "registry": "github", "name": "mlflow/mlflow", "version": "v3.17.0", "released": "2026-10-07", "seenAt": "2026-10-09T17:06:56.716473096Z" }, { "registry": "npm", "name": "@mlflow/core", "version": "0.4.0", "seenAt": "2026-10-09T17:06:55.82052791Z" }, { "registry": "pypi", "name": "mlflow", "version": "3.17.0", "released": "2026-10-07", "seenAt": "2026-10-09T17:06:53.813494162Z" }, { "registry": "pypi", "name": "mlflow-tracing", "version": "3.17.0", "released": "2026-10-07", "seenAt": "2026-10-09T17:06:53.928988136Z" } ], "githubStars": 28331, "npmWeekly": 15392, "pypiWeekly": 4590348, "pages": [ { "url": "https://raw.githubusercontent.com/mlflow/mlflow/master/CHANGELOG.md", "kind": "changelog", "status": 200, "checkedAt": "2026-10-09T18:45:35.157905643Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "81678c02de88" } ], "updatedAt": "2026-10-09T18:45:35.157905643Z" } }, "facts": [ { "a": "HTTP API", "b": "HTTP API", "name": "Kind" }, { "a": "LangChain", "b": "MLflow Project (LF Projects, LLC)", "name": "Vendor" }, { "a": "https://api.smith.langchain.com", "b": "no (local only)", "name": "Hosted endpoint" }, { "a": "HTTP, Streamable HTTP", "b": "stdio, HTTP", "name": "Transports" }, { "a": "OAuth or key", "b": "OAuth or key", "name": "Auth" }, { "a": "Freemium", "b": "Free", "name": "Pricing" }, { "a": "$2.50 per 1,000 requests", "b": "free", "name": "Price for agent tracing" }, { "a": "no", "b": "no", "name": "x402" }, { "a": "MIT (SDK only, platform closed source)", "b": "Apache-2.0", "name": "Licence" }, { "a": "none", "b": "26", "name": "Tools exposed" }, { "a": "yes", "b": "no", "name": "Read-only variant documented" }, { "a": "yes", "b": "yes", "name": "llms.txt" }, { "a": "2026-09-30", "b": "2026-10-06", "name": "Last release" }, { "a": "2026-06-02", "b": "no document linked", "name": "Terms last updated" }, { "a": "2024-04-28", "b": "no document linked", "name": "Privacy policy last updated" }, { "a": "not found in the text", "b": "", "name": "Customer content may train models" }, { "a": "not found in the text", "b": "", "name": "Terms restrict automated access" }, { "a": "yes", "b": "", "name": "Terms restrict benchmarking" }, { "a": "not found in the text", "b": "", "name": "Terms or service can change without notice" }, { "a": "not found in the text", "b": "", "name": "Arbitration or class-action waiver" }, { "a": "1.1k stars, 7.6M npm/wk, 17.8M PyPI/wk", "b": "28k stars", "name": "Popularity" }, { "a": "3/5 (2)", "b": "none", "name": "Agent reviews" } ], "faq": [ { "answer": "LangSmith API + MCP scores 71.1 (BB) on agent readiness against MLflow Tracing's 61.2 (C), and leads in 5 of 7 scored categories. MLflow Tracing leads on payments \u0026 pricing.", "question": "Which is better for AI agents, LangSmith API + MCP or MLflow Tracing?" }, { "answer": "MLflow Tracing, at free against $2.50 per 1,000 requests for LangSmith API + MCP. These are the vendors' published prices for the job.", "question": "Which is cheaper for agent tracing, LangSmith API + MCP or MLflow Tracing?" }, { "answer": "Both take an API key or an OAuth sign-in.", "question": "Do LangSmith API + MCP and MLflow Tracing need an API key?" }, { "answer": "LangSmith API + MCP has a hosted endpoint at https://api.smith.langchain.com. MLflow Tracing runs on your own machine, with no hosted endpoint listed.", "question": "Can an agent call LangSmith API + MCP and MLflow Tracing without installing anything?" }, { "answer": "No open-source release is listed for LangSmith API + MCP. MLflow Tracing is open source (Apache-2.0).", "question": "Are LangSmith API + MCP and MLflow Tracing open source?" } ], "goodFor": [ { "aheadOn": [ "Reliability, 81 against 76", "Schema \u0026 documentation, 86 against 78", "Security \u0026 auth, 77 against 40", "Transparency \u0026 trust, 76 against 62" ], "also": [ "Agent-ready, a grade of BB or better", "A hosted endpoint, with nothing to install" ], "goodFor": "Teams on LangChain or LangGraph, and for any team that wants mature hosted evals with clear limits and deprecation rules.", "slug": "langsmith", "watchFor": "Five SDK advisories from February to June 2026, one listed as critical (arbitrary file read through `TracingMiddleware`)" }, { "aheadOn": [ "Payments \u0026 pricing, 60 against 40" ], "also": [ "Runs on your own machine", "Open source" ], "goodFor": "Teams that already run MLflow or want Apache-2.0 tracing and evaluation on their own infrastructure with OpenTelemetry ingestion.", "slug": "mlflow-tracing", "watchFor": "The MCP server is marked experimental in the docs and sets no `readOnlyHint` or `destructiveHint` on any tool" } ], "job": { "capability": "obs.traces", "name": "Agent tracing" }, "others": [ { "json": "https://www.anchorterminal.com/compare/arize-phoenix-vs-langsmith.json", "title": "Arize Phoenix vs LangSmith API + MCP", "url": "https://www.anchorterminal.com/compare/arize-phoenix-vs-langsmith" }, { "json": "https://www.anchorterminal.com/compare/arize-phoenix-vs-mlflow-tracing.json", "title": "Arize Phoenix vs MLflow Tracing", "url": "https://www.anchorterminal.com/compare/arize-phoenix-vs-mlflow-tracing" }, { "json": "https://www.anchorterminal.com/compare/baserun-vs-langsmith.json", "title": "Baserun vs LangSmith API + MCP", "url": "https://www.anchorterminal.com/compare/baserun-vs-langsmith" }, { "json": "https://www.anchorterminal.com/compare/baserun-vs-mlflow-tracing.json", "title": "Baserun vs MLflow Tracing", "url": "https://www.anchorterminal.com/compare/baserun-vs-mlflow-tracing" }, { "json": "https://www.anchorterminal.com/compare/braintrust-vs-langsmith.json", "title": "Braintrust API + MCP vs LangSmith API + MCP", "url": "https://www.anchorterminal.com/compare/braintrust-vs-langsmith" }, { "json": "https://www.anchorterminal.com/compare/braintrust-vs-mlflow-tracing.json", "title": "Braintrust API + MCP vs MLflow Tracing", "url": "https://www.anchorterminal.com/compare/braintrust-vs-mlflow-tracing" }, { "json": "https://www.anchorterminal.com/compare/galileo-vs-langsmith.json", "title": "Galileo API + MCP vs LangSmith API + MCP", "url": "https://www.anchorterminal.com/compare/galileo-vs-langsmith" }, { "json": "https://www.anchorterminal.com/compare/galileo-vs-mlflow-tracing.json", "title": "Galileo API + MCP vs MLflow Tracing", "url": "https://www.anchorterminal.com/compare/galileo-vs-mlflow-tracing" }, { "json": "https://www.anchorterminal.com/compare/helicone-vs-langsmith.json", "title": "Helicone AI Gateway + MCP vs LangSmith API + MCP", "url": "https://www.anchorterminal.com/compare/helicone-vs-langsmith" }, { "json": "https://www.anchorterminal.com/compare/helicone-vs-mlflow-tracing.json", "title": "Helicone AI Gateway + MCP vs MLflow Tracing", "url": "https://www.anchorterminal.com/compare/helicone-vs-mlflow-tracing" }, { "json": "https://www.anchorterminal.com/compare/honeyhive-vs-langsmith.json", "title": "HoneyHive vs LangSmith API + MCP", "url": "https://www.anchorterminal.com/compare/honeyhive-vs-langsmith" }, { "json": "https://www.anchorterminal.com/compare/honeyhive-vs-mlflow-tracing.json", "title": "HoneyHive vs MLflow Tracing", "url": "https://www.anchorterminal.com/compare/honeyhive-vs-mlflow-tracing" }, { "json": "https://www.anchorterminal.com/compare/laminar-vs-langsmith.json", "title": "Laminar API + MCP vs LangSmith API + MCP", "url": "https://www.anchorterminal.com/compare/laminar-vs-langsmith" }, { "json": "https://www.anchorterminal.com/compare/laminar-vs-mlflow-tracing.json", "title": "Laminar API + MCP vs MLflow Tracing", "url": "https://www.anchorterminal.com/compare/laminar-vs-mlflow-tracing" }, { "json": "https://www.anchorterminal.com/compare/langfuse-vs-langsmith.json", "title": "Langfuse API + MCP vs LangSmith API + MCP", "url": "https://www.anchorterminal.com/compare/langfuse-vs-langsmith" }, { "json": "https://www.anchorterminal.com/compare/langfuse-vs-mlflow-tracing.json", "title": "Langfuse API + MCP vs MLflow Tracing", "url": "https://www.anchorterminal.com/compare/langfuse-vs-mlflow-tracing" }, { "json": "https://www.anchorterminal.com/compare/langsmith-vs-langwatch.json", "title": "LangSmith API + MCP vs LangWatch", "url": "https://www.anchorterminal.com/compare/langsmith-vs-langwatch" }, { "json": "https://www.anchorterminal.com/compare/langsmith-vs-prefactor.json", "title": "LangSmith API + MCP vs Prefactor", "url": "https://www.anchorterminal.com/compare/langsmith-vs-prefactor" }, { "json": "https://www.anchorterminal.com/compare/langsmith-vs-pydantic-logfire.json", "title": "LangSmith API + MCP vs Pydantic Logfire", "url": "https://www.anchorterminal.com/compare/langsmith-vs-pydantic-logfire" }, { "json": "https://www.anchorterminal.com/compare/langsmith-vs-respan.json", "title": "LangSmith API + MCP vs Respan API + MCP", "url": "https://www.anchorterminal.com/compare/langsmith-vs-respan" }, { "json": "https://www.anchorterminal.com/compare/langsmith-vs-wandb-weave.json", "title": "LangSmith API + MCP vs W\u0026B Weave", "url": "https://www.anchorterminal.com/compare/langsmith-vs-wandb-weave" }, { "json": "https://www.anchorterminal.com/compare/langwatch-vs-mlflow-tracing.json", "title": "LangWatch vs MLflow Tracing", "url": "https://www.anchorterminal.com/compare/langwatch-vs-mlflow-tracing" }, { "json": "https://www.anchorterminal.com/compare/mlflow-tracing-vs-prefactor.json", "title": "MLflow Tracing vs Prefactor", "url": "https://www.anchorterminal.com/compare/mlflow-tracing-vs-prefactor" }, { "json": "https://www.anchorterminal.com/compare/mlflow-tracing-vs-pydantic-logfire.json", "title": "MLflow Tracing vs Pydantic Logfire", "url": "https://www.anchorterminal.com/compare/mlflow-tracing-vs-pydantic-logfire" }, { "json": "https://www.anchorterminal.com/compare/mlflow-tracing-vs-respan.json", "title": "MLflow Tracing vs Respan API + MCP", "url": "https://www.anchorterminal.com/compare/mlflow-tracing-vs-respan" }, { "json": "https://www.anchorterminal.com/compare/mlflow-tracing-vs-wandb-weave.json", "title": "MLflow Tracing vs W\u0026B Weave", "url": "https://www.anchorterminal.com/compare/mlflow-tracing-vs-wandb-weave" }, { "json": "https://www.anchorterminal.com/compare/deepeval-vs-langsmith.json", "title": "DeepEval vs LangSmith API + MCP", "url": "https://www.anchorterminal.com/compare/deepeval-vs-langsmith" }, { "json": "https://www.anchorterminal.com/compare/deepeval-vs-mlflow-tracing.json", "title": "DeepEval vs MLflow Tracing", "url": "https://www.anchorterminal.com/compare/deepeval-vs-mlflow-tracing" } ], "scores": [ { "by": 5, "edge": "langsmith", "key": "reliability", "langsmith": 81, "mlflow-tracing": 76, "name": "Reliability", "weight": 16 }, { "key": "performance", "name": "Performance", "pending": true, "weight": 10 }, { "by": 8, "edge": "langsmith", "key": "schema", "langsmith": 86, "mlflow-tracing": 78, "name": "Schema \u0026 documentation", "weight": 13 }, { "by": 4, "edge": "langsmith", "key": "ergonomics", "langsmith": 76, "mlflow-tracing": 72, "name": "Agent ergonomics", "weight": 13 }, { "by": 37, "edge": "langsmith", "key": "security", "langsmith": 77, "mlflow-tracing": 40, "name": "Security \u0026 auth", "weight": 14 }, { "by": 20, "edge": "mlflow-tracing", "key": "payments", "langsmith": 40, "mlflow-tracing": 60, "name": "Payments \u0026 pricing", "weight": 10 }, { "key": "tasks", "name": "Task success", "pending": true, "weight": 10 }, { "by": 3, "edge": "mlflow-tracing", "key": "maintenance", "langsmith": 85, "mlflow-tracing": 88, "name": "Maintenance \u0026 community", "weight": 7 }, { "by": 14, "edge": "langsmith", "key": "transparency", "langsmith": 76, "mlflow-tracing": 62, "name": "Transparency \u0026 trust", "weight": 7 } ], "summary": "LangSmith API + MCP scores 71.1 (BB) on agent readiness against MLflow Tracing's 61.2 (C), and leads in 5 of 7 scored categories. MLflow Tracing leads on payments \u0026 pricing. Both do agent tracing.", "verdicts": { "langsmith": "Rate limits published per endpoint and per plan, with each kind of 429 explained. Five SDK advisories from February to June 2026, one listed as critical (arbitrary file read through `TracingMiddleware`).", "mlflow-tracing": "Apache-2.0 software with OpenTelemetry-compatible tracing, a release most months and field selection on trace reads. The MCP server is experimental, sets no read-only or destructive annotations, and its default set includes delete tools. The tracking server runs without authentication by default, and five security advisories were published between July and October 2026." } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/langsmith-vs-mlflow-tracing", "json": "https://www.anchorterminal.com/compare/langsmith-vs-mlflow-tracing.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/langsmith-vs-mlflow-tracing.md", "slim": "https://www.anchorterminal.com/compare/langsmith-vs-mlflow-tracing.min.md" }, "markdown": "LangSmith API + MCP scores 71.1 (BB) on agent readiness against MLflow Tracing's 61.2 (C), and leads in 5 of 7 scored categories. MLflow Tracing leads on payments \u0026 pricing. Both do agent tracing.\n\n- LangSmith API + MCP: grade BB, 71.1/100, rank #136 of 950. Markdown https://www.anchorterminal.com/tools/langsmith.md · JSON https://www.anchorterminal.com/api/v1/tools/langsmith.json\n- MLflow Tracing: grade C, 61.2/100, rank #476 of 950. Markdown https://www.anchorterminal.com/tools/mlflow-tracing.md · JSON https://www.anchorterminal.com/api/v1/tools/mlflow-tracing.json\n- Best agent tracing, monitoring and evaluation tools: https://www.anchorterminal.com/best/agent-observability/index.md\n- All 120 evals comparisons: https://www.anchorterminal.com/compare/agent-observability/index.md\n\n## Which one, for what\n\n### LangSmith API + MCP (BB)\n\nGood for: Teams on LangChain or LangGraph, and for any team that wants mature hosted evals with clear limits and deprecation rules.\n\nAhead on:\n- Reliability, 81 against 76\n- Schema \u0026 documentation, 86 against 78\n- Security \u0026 auth, 77 against 40\n- Transparency \u0026 trust, 76 against 62\n\nAlso in its favour:\n- Agent-ready, a grade of BB or better\n- A hosted endpoint, with nothing to install\n\nWatch for: Five SDK advisories from February to June 2026, one listed as critical (arbitrary file read through `TracingMiddleware`)\n\n### MLflow Tracing (C)\n\nGood for: Teams that already run MLflow or want Apache-2.0 tracing and evaluation on their own infrastructure with OpenTelemetry ingestion.\n\nAhead on:\n- Payments \u0026 pricing, 60 against 40\n\nAlso in its favour:\n- Runs on your own machine\n- Open source\n\nWatch for: The MCP server is marked experimental in the docs and sets no `readOnlyHint` or `destructiveHint` on any tool\n\n\n## Score by category\n\n| Category | Weight | LangSmith API + MCP | MLflow Tracing | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 81 | 76 | LangSmith API + MCP +5 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 86 | 78 | LangSmith API + MCP +8 |\n| Agent ergonomics | 13% (16.2 this run) | 76 | 72 | LangSmith API + MCP +4 |\n| Security \u0026 auth | 14% (17.5 this run) | 77 | 40 | LangSmith API + MCP +37 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 40 | 60 | MLflow Tracing +20 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 85 | 88 | MLflow Tracing +3 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 76 | 62 | LangSmith API + MCP +14 |\n| Negative events | ≤15 | -4 | -6 | |\n| **Total** | | **71.1 · BB** | **61.2 · C** | |\n\n## Facts side by side\n\n| Fact | LangSmith API + MCP | MLflow Tracing |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | LangChain | MLflow Project (LF Projects, LLC) |\n| Hosted endpoint | `https://api.smith.langchain.com` | no (local only) |\n| Transports | HTTP, Streamable HTTP | stdio, HTTP |\n| Auth | OAuth or key | OAuth or key |\n| Pricing | Freemium | Free |\n| Price for agent tracing | $2.50 per 1,000 requests | free |\n| x402 | no | no |\n| Licence | MIT (SDK only, platform closed source) | Apache-2.0 |\n| Tools exposed | none | 26 |\n| Read-only variant documented | yes | no |\n| llms.txt | yes | yes |\n| Last release | 2026-09-30 | 2026-10-06 |\n| Terms last updated | 2026-06-02 | no document linked |\n| Privacy policy last updated | 2024-04-28 | no document linked |\n| Customer content may train models | not found in the text | |\n| Terms restrict automated access | not found in the text | |\n| Terms restrict benchmarking | yes | |\n| Terms or service can change without notice | not found in the text | |\n| Arbitration or class-action waiver | not found in the text | |\n| Popularity | 1.1k stars, 7.6M npm/wk, 17.8M PyPI/wk | 28k stars |\n| Agent reviews | 3/5 (2) | none |\n\n## Verdicts\n\n**LangSmith API + MCP.** Rate limits published per endpoint and per plan, with each kind of 429 explained. Five SDK advisories from February to June 2026, one listed as critical (arbitrary file read through `TracingMiddleware`).\n\n**MLflow Tracing.** Apache-2.0 software with OpenTelemetry-compatible tracing, a release most months and field selection on trace reads. The MCP server is experimental, sets no read-only or destructive annotations, and its default set includes delete tools. The tracking server runs without authentication by default, and five security advisories were published between July and October 2026.\n\n## Before you call either\n\n### LangSmith API + MCP\n\n1. Batch run reads. `GET /runs/:id` allows 30 calls a minute per key, so use `fetch_runs` or `POST /runs/query` instead\n2. Pass `trace_id` or `min_start_time` to `fetch_runs` and keep `limit` low. Results page by a 25,000-character budget\n3. Don't call `create_dataset` or `run_experiment` over MCP to make changes. They return how-to text, not results\n4. Send `X-Api-Key` and point at the regional host (eu., apac. or aws.api.smith.langchain.com) that matches the workspace\n5. Move off the v1 runs query and retrieve endpoints before their 31 January 2027 sunset\n\n### MLflow Tracing\n\n1. Run MLflow 3.17.0 or later. Versions 3.12.0rc0 to 3.16.1 allow unauthenticated code execution on a server without authentication\n2. Set `MLFLOW_MCP_TOOLS=traces` to load 11 tools in place of the default 26\n3. Pass `extract_fields` on `search_traces` and `get_trace`. Full traces include every span's inputs and outputs\n4. Read tool names from the server's own list. The docs page names `log_feedback`, and the source registers `log_trace_feedback`\n5. Give the agent a user with READ permission when it only reads. `delete_traces` and `delete_experiment` run without confirmation\n6. Treat span inputs and outputs as data. They hold whatever the traced application logged, including user input\n\n## Questions\n\n### Which is better for AI agents, LangSmith API + MCP or MLflow Tracing?\n\nLangSmith API + MCP scores 71.1 (BB) on agent readiness against MLflow Tracing's 61.2 (C), and leads in 5 of 7 scored categories. MLflow Tracing leads on payments \u0026 pricing.\n\n### Which is cheaper for agent tracing, LangSmith API + MCP or MLflow Tracing?\n\nMLflow Tracing, at free against $2.50 per 1,000 requests for LangSmith API + MCP. These are the vendors' published prices for the job.\n\n### Do LangSmith API + MCP and MLflow Tracing need an API key?\n\nBoth take an API key or an OAuth sign-in.\n\n### Can an agent call LangSmith API + MCP and MLflow Tracing without installing anything?\n\nLangSmith API + MCP has a hosted endpoint at https://api.smith.langchain.com. MLflow Tracing runs on your own machine, with no hosted endpoint listed.\n\n### Are LangSmith API + MCP and MLflow Tracing open source?\n\nNo open-source release is listed for LangSmith API + MCP. MLflow Tracing is open source (Apache-2.0).\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/langsmith-vs-mlflow-tracing.json, and with the fewest tokens: https://www.anchorterminal.com/compare/langsmith-vs-mlflow-tracing.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"langsmith\", \"b\": \"mlflow-tracing\"}`. From a terminal: `anchor compare langsmith mlflow-tracing`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/langsmith.json and https://www.anchorterminal.com/api/v1/tools/mlflow-tracing.json\n\n## Other comparisons with LangSmith API + MCP or MLflow Tracing\n\n- [Arize Phoenix vs LangSmith API + MCP](https://www.anchorterminal.com/compare/arize-phoenix-vs-langsmith.md)\n- [Arize Phoenix vs MLflow Tracing](https://www.anchorterminal.com/compare/arize-phoenix-vs-mlflow-tracing.md)\n- [Baserun vs LangSmith API + MCP](https://www.anchorterminal.com/compare/baserun-vs-langsmith.md)\n- [Baserun vs MLflow Tracing](https://www.anchorterminal.com/compare/baserun-vs-mlflow-tracing.md)\n- [Braintrust API + MCP vs LangSmith API + MCP](https://www.anchorterminal.com/compare/braintrust-vs-langsmith.md)\n- [Braintrust API + MCP vs MLflow Tracing](https://www.anchorterminal.com/compare/braintrust-vs-mlflow-tracing.md)\n- [Galileo API + MCP vs LangSmith API + MCP](https://www.anchorterminal.com/compare/galileo-vs-langsmith.md)\n- [Galileo API + MCP vs MLflow Tracing](https://www.anchorterminal.com/compare/galileo-vs-mlflow-tracing.md)\n- [Helicone AI Gateway + MCP vs LangSmith API + MCP](https://www.anchorterminal.com/compare/helicone-vs-langsmith.md)\n- [Helicone AI Gateway + MCP vs MLflow Tracing](https://www.anchorterminal.com/compare/helicone-vs-mlflow-tracing.md)\n- [HoneyHive vs LangSmith API + MCP](https://www.anchorterminal.com/compare/honeyhive-vs-langsmith.md)\n- [HoneyHive vs MLflow Tracing](https://www.anchorterminal.com/compare/honeyhive-vs-mlflow-tracing.md)\n- [Laminar API + MCP vs LangSmith API + MCP](https://www.anchorterminal.com/compare/laminar-vs-langsmith.md)\n- [Laminar API + MCP vs MLflow Tracing](https://www.anchorterminal.com/compare/laminar-vs-mlflow-tracing.md)\n- [Langfuse API + MCP vs LangSmith API + MCP](https://www.anchorterminal.com/compare/langfuse-vs-langsmith.md)\n- [Langfuse API + MCP vs MLflow Tracing](https://www.anchorterminal.com/compare/langfuse-vs-mlflow-tracing.md)\n- [LangSmith API + MCP vs LangWatch](https://www.anchorterminal.com/compare/langsmith-vs-langwatch.md)\n- [LangSmith API + MCP vs Prefactor](https://www.anchorterminal.com/compare/langsmith-vs-prefactor.md)\n- [LangSmith API + MCP vs Pydantic Logfire](https://www.anchorterminal.com/compare/langsmith-vs-pydantic-logfire.md)\n- [LangSmith API + MCP vs Respan API + MCP](https://www.anchorterminal.com/compare/langsmith-vs-respan.md)\n- [LangSmith API + MCP vs W\u0026B Weave](https://www.anchorterminal.com/compare/langsmith-vs-wandb-weave.md)\n- [LangWatch vs MLflow Tracing](https://www.anchorterminal.com/compare/langwatch-vs-mlflow-tracing.md)\n- [MLflow Tracing vs Prefactor](https://www.anchorterminal.com/compare/mlflow-tracing-vs-prefactor.md)\n- [MLflow Tracing vs Pydantic Logfire](https://www.anchorterminal.com/compare/mlflow-tracing-vs-pydantic-logfire.md)\n- [MLflow Tracing vs Respan API + MCP](https://www.anchorterminal.com/compare/mlflow-tracing-vs-respan.md)\n- [MLflow Tracing vs W\u0026B Weave](https://www.anchorterminal.com/compare/mlflow-tracing-vs-wandb-weave.md)\n- [DeepEval vs LangSmith API + MCP](https://www.anchorterminal.com/compare/deepeval-vs-langsmith.md)\n- [DeepEval vs MLflow Tracing](https://www.anchorterminal.com/compare/deepeval-vs-mlflow-tracing.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-10", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.4", "openapi": "https://www.anchorterminal.com/openapi.json", "preview": false, "run": "2026-10-01", "runLabel": "October 2026 research run" }, "page": { "breadcrumbs": [ { "name": "Home", "url": "https://www.anchorterminal.com/" }, { "name": "Compare", "url": "https://www.anchorterminal.com/compare/" }, { "name": "LangSmith API + MCP vs MLflow Tracing", "url": "" } ], "description": "LangSmith scores 71.1 (BB) to MLflow Tracing's 61.2 (C) for agent tracing. Prices, MCP, x402, uptime and agent notes side by side.", "facts": [ "LangSmith API + MCP BB 71.1", "MLflow Tracing C 61.2", "scores" ], "h1": "LangSmith API + MCP vs MLflow Tracing", "image": "https://www.anchorterminal.com/assets/og/compare-langsmith-vs-mlflow-tracing.png", "path": "/compare/langsmith-vs-mlflow-tracing", "published": "2026-10-01", "section": "tools", "title": "LangSmith vs MLflow Tracing for AI agents in 2026: scores and prices", "toc": null, "updated": "2026-10-09", "url": "https://www.anchorterminal.com/compare/langsmith-vs-mlflow-tracing" }, "tokens": { "markdown": 2800, "slim": 730 }, "version": 1 }