the short answer
The main Raindrop alternatives are Failproof AI for finding production failures and turning tested fixes into policies, Latitude for an MIT-licensed self-hosted platform, Judgment Labs for rubric judges, Galileo for built-in evaluations, Future AGI for gateway guardrails, Langfuse for open-source tracing and evals, and Sentry if your team already uses it. Stay on Raindrop if you rely on Experiments or Signals; none of these has the same cohort comparison.
- Raindrop Pro
- $299/month plus $0.003 per event to 1M
- Alerts
- Slack only: signal thresholds, daily digest, Agent Briefs
- Blocking
- None; detects and alerts after the fact
- Self-host
- VPC rolling out with a select group of partners
Why Teams Look Past Raindrop
Raindrop classifies production agent events for silent failures with its own model, rd-signal-2, ranks them into Issues, and lets you compare cohorts with Experiments. Teams tend to compare alternatives when the price, response workflow or deployment model does not fit.
- The entry price is $299 a month before usage. Pro includes no event allowance; every event is metered at $0.003 up to 1M, then $0.002. Hobby is free but stops ingesting at 1,000 events a month, and Issue Detection and Experiments are preview-only there.
- The workflow ends at detection and investigation. Raindrop surfaces Issues and root-cause context, but teams need another workflow to apply and enforce the fix on a later run.
- Self-hosting is not generally available. Raindrop 2.0 is "rolling VPC out with a select group of initial partners". SSO, SAML and audit logs are Enterprise features.
- Alerts go to Slack only. Signal thresholds, the daily digest and scheduled Agent Briefs are delivered to Slack. Teams that page through email, webhooks or an incident tool need a bridge.
The Shortlist
Failproof AI - If You Want to Find Failures and Fix Them
Failproof AI traces agent sessions and makes the underlying events queryable, from model calls to tool results. Cloud evaluations can use code checks, LLM judges or your existing evaluation suite. Automated audits then look across production sessions, group related failures into findings and recommend what to fix. Alerts can reach email, Slack, webhooks or the dashboard.
Once a fix has been tested, Failproof can turn it into a behavioral policy for supported agent harnesses such as Claude Code, Codex, Cursor and GitHub Copilot CLI. The policy can steer the agent or deny a risky tool call before it runs. The free tier supports evaluation and failure analysis, while Team is $99 a month and SSO starts on Scale.
- Limits: Failproof AI does not provide a cohort-comparison feature equivalent to Raindrop Experiments.
- Best for: teams that need to investigate failures across production traffic, alert the right owner and carry a tested fix into runtime behavior.
Latitude - If You Want It Open Source and Self-Hosted
Latitude traces agents over OpenTelemetry, scores sessions with conditions, an LLM judge or custom JavaScript, supports human annotation, and sends Claude Code or Cursor to propose pull requests through Agent Dispatch. The whole platform is MIT and self-hosts for free; the managed cloud is free with unlimited seats, then $99 a month. Limits: no runtime blocking, managed cloud in the EU only, and a "credit" is not defined on its pricing page. Best for: teams that want the platform on their own infrastructure.
Judgment Labs - If Judging Is the Whole Job
Judgment Labs pairs the Apache-2.0 judgeval SDK with a hosted platform for rubric-driven Agent Judge, Code Judge and Behavior Discovery, scoring a sample of completed traces. Limits: no published pricing, demo-first onboarding, self-hosting listed as coming soon and no runtime blocking. Best for: teams that want specialist agent judges and are comfortable buying through sales.
Galileo - If You Want Built-in Metrics and an Enterprise Vendor
Galileo ships more than 20 ready-made evaluations, Luna-2 evaluation models and CLHF for tuning metrics from a few labels. Cisco acquired the company in May 2026, and its release notes now call the product Splunk Agent Observability. The Free tier, with 5,000 traces, is self-serve; Pro at $100 a month and Enterprise both start with a demo. Limits: hosted real-time guardrails and Luna-2 are Enterprise-only, while the open-source Agent Control service is yours to run. Best for: larger teams that want ready-made metrics and buy through sales.
Future AGI - If You Want Evals, Simulation and a Gateway in One
Future AGI has an Apache-2.0 core with built-in evaluators and its own evaluator models, simulation, prompt optimization and a gateway whose Protect scanners can block model I/O and gateway tool calls. Limits: tool-call enforcement covers traffic through its gateway, some repository code uses an enterprise licence, and the self-hosted stack contains many services. Best for: teams that want breadth and already route model calls through one place.
Langfuse - If You Want Open-Source Tracing and Prompt Management
Langfuse is an open-source LLM engineering platform with an MIT core and separately licensed enterprise features. It includes tracing, prompt management and evaluations through LLM-based checks, code, user feedback or manual labels. Self-host for free, or use the cloud with a free Hobby tier and Core from $29 a month. Limits: it does not provide automatic recurring-failure discovery or runtime blocking. Best for: teams that want an established open-source base and will define their own quality checks.
Sentry - If You Already Run It
Sentry traces LLM calls, tool executions, MCP interactions and handoffs as spans with inputs, outputs, token use, cost and timing. It auto-instruments the OpenAI Agents SDK, Vercel AI SDK, LangChain, LangGraph, Anthropic and other common stacks. Limits: Sentry focuses on operational telemetry. Measuring wrong answers, missed goals or poor tool choices requires quality evaluations in addition to tracing. Best for: teams that already use Sentry and primarily need agent errors, latency and cost beside their existing application issues.
At a Glance
| Raindrop | Failproof AI | Latitude | Judgment Labs | Langfuse | |
|---|---|---|---|---|---|
| Silent-failure detection | Signals, Issues | Code checks, LLM judges, your existing evals, audits | Evals, Flaggers, signals | Judges, Behavior Discovery | Evals you configure |
| Blocks an action | No | At the hook, before it runs | No | No | Not listed |
| Cohort A/B on production | Experiments | No | No | No | Not listed |
| Free tier | 1,000 events, then stops | 5,000 runs | 20K credits | Not published | 50k units |
| Entry paid plan | $299/mo + events | $99/mo | $99/mo | Not published | $29/mo |
| Self-host | Partner VPC | Enterprise | Free, MIT | Coming soon | Free, MIT core |
When to Stay on Raindrop
If your agent is a consumer product with real daily traffic, and the questions you ask are "is this failure getting rarer" and "did the new prompt help", Raindrop is hard to replace. Experiments compares a baseline and an experiment cohort of logged events by model, prompt version, date range or feature flag, and reports the change in signal rates; nothing else on this list does that. Signals let a product manager describe a failure in a sentence and have it classified across every new event. Slack-only alerts are a real limit only if your on-call does not live in Slack.
You do not have to replace Raindrop to fill a gap. Failproof AI can run code-based and LLM-based evaluations, analyze recurring failures with trace evidence, route findings through alerts and ownership, and help verify the fix. For supported high-risk agent actions, a tested policy can also run at the hook layer. See Failproof AI vs Raindrop. If price is the concern, check the arithmetic against your own event volume before moving.
If You Do Switch
Raindrop accepts OpenTelemetry traces over OTLP/HTTP, and Latitude traces over OpenTelemetry too, so instrumentation built on OTel moves more easily than instrumentation built on a vendor SDK. What does not move is the tuning: Signals you refined by labeling have to be rebuilt as evaluations or judges elsewhere, and their history starts again. Export the labeled examples first - they are the most reusable thing you own.
FAQ
Is there a free alternative to Raindrop?
Yes. Latitude and Langfuse can be self-hosted for free under open-source licences, and both have free cloud tiers. Failproof AI has a free cloud tier with 5,000 runs a month plus an MIT CLI for local enforcement. Raindrop's own Hobby plan is free but stops ingesting at 1,000 events a month.
Which Raindrop alternative can block agent actions?
Failproof AI blocks at the agent hook layer before a tool runs, in Claude Code, Codex, Cursor and other supported harnesses. Future AGI blocks tool calls routed through its gateway. Galileo lists real-time guardrails on Enterprise, and its open-source Agent Control checks LLM and tool inputs and outputs with deny, steer, warn, log or allow decisions. Raindrop, Latitude, Judgment Labs and Langfuse detect after the fact.
Which alternative has something like Raindrop Experiments?
None of the tools on this list publishes the same workflow: comparing two cohorts of logged production events by model, prompt, date range or feature flag and reporting signal-rate changes. Evaluation platforms commonly compare versions on controlled datasets, which answers a related but different question.
Get Started
Failproof AI is free to start. It finds recurring failure modes across agent sessions using code-based and LLM-based evaluations, groups the evidence into findings, and recommends fixes. Bring the eval suite you already have, alert the right owner when behavior drifts, and turn a tested fix into a policy that prevents the failure from recurring. See pricing for the tiers.
Sources
Checked against each vendor's own site and docs on 2026-09-14. Products change; if a detail here is out of date, tell us at support@befailproof.ai.
- Raindrop docs: Plans
- Raindrop docs: Alerts
- Raindrop docs: Experiments
- Introducing Raindrop 2.0 (Raindrop blog, June 2026)
- Raindrop docs index
- Latitude pricing
- latitude-llm on GitHub
- Judgment Labs docs: Self-hosting
- Galileo pricing
- Galileo release notes (rename to Splunk Agent Observability)
- Announcing Agent Control (Galileo blog)
- Future AGI docs: Protect
- Future AGI on GitHub (README)
- Future AGI docs: Self-hosting requirements
- Langfuse pricing
- Langfuse on GitHub
- Sentry: AI agent tracing