Agentic Index
Braintrust vs W&B Weave (2026)
Braintrust and Weights and Biases Weave both do LLM evaluation and observability, priced on different meters: Braintrust runs a free Starter (one gigabyte of processed data, ten thousand scores a month) then Pro at 249 dollars a month with overage at 3 dollars a gigabyte and 1.50 dollars per thousand scores, with bring your own cloud and self hosting at enterprise, while Weave has a free tier then Pro around 60 dollars a month plus usage meters (storage at three cents a gigabyte, trace ingestion at ten cents a megabyte) and now sits inside CoreWeave after the 2025 acquisition. Braintrust is the eval first purist choice; Weave fits teams already living in the Weights and Biases ML stack.
| At a glance | Braintrust | W&B Weave |
|---|---|---|
| Category | Agent infrastructure | Agent infrastructure |
| Entry price | Free Starter (1 GB data, 10K scores) · Pro $249/mo | Free tier; Pro about $60/mo plus usage meters; Enterprise custom |
| Free / trial | Free Starter plan, no card (1 GB data, 10K scores/mo, 14 day retention) | Free tier plus free Pro for academics; free trial to estimate ingestion |
| Pricing confidence | public exact | public partial |
| Feature | ||
|---|---|---|
| Action & orchestration | ||
|
Integrations & Tool Calling Ability to connect agents to real systems through native integrations, OAuth-authenticated actions, custom tools, APIs, webhooks, or MCP-compatible tools. |
Full / Explicit | Full / Explicit |
|
Workflow Orchestration Ability to sequence, branch, retry, route, and combine deterministic workflow nodes with autonomous agent steps. |
No / Not documented | No / Not documented |
|
Triggers & Channel Coverage How agents wake up and where they work: schedules, webhooks, message events, CRM events, inbox events, chat, email, voice, and collaboration tools. |
No / Not documented | No / Not documented |
| Knowledge & context | ||
|
Knowledge Grounding & RAG Ability to ground agent behavior in company data through document ingestion, retrieval, external knowledge APIs, semantic search, or RAG layers. |
Partial | No / Not documented |
|
Memory & State Persistence Ability to persist context across a run, conversation, workflow, user, team, or longer-term memory layer. |
No / Not documented | No / Not documented |
| Control & trust | ||
|
Human Oversight & Guardrails Approval steps, consent checkpoints, escalation rules, structured guardrails, policy constraints, and pause/resume controls. |
Full / Explicit | Partial |
|
Security, Identity & Governance RBAC, SSO, auditability, encryption, least-privilege tool access, compliance posture, and data handling policy. |
Partial | Full / Explicit |
|
Observability & Auditability Traces, logs, execution histories, metrics, audit events, and debugging detail for production agent behavior. |
Full / Explicit | Full / Explicit |
|
Deployment & Data Residency Deployment modes and options, including SaaS, dedicated cloud, VPC, on-prem, hybrid, local runtime, and self-hosting. |
Full / Explicit | Full / Explicit |
| Solution readiness | ||
|
Prebuilt Agents, Templates & Packs Ready-made workflows, packaged employees, templates, blueprints, industry solutions, and role-specific agents that reduce time-to-value. |
No / Not documented | No / Not documented |
| Platform extensibility | ||
|
Model Flexibility & Routing Ability to work across multiple foundation models, route tasks to different models, or let buyers bring their own providers and keys. |
Full / Explicit | Partial |
|
APIs, SDKs & MCP Extensibility Composability layer: stable APIs, SDKs, MCP tool consumption/serving, custom tools, and integration into internal systems. |
Full / Explicit | Full / Explicit |
|
Testing, Debugging & Optimization Testing, debugging, scoring, retries, fallbacks, quality gates, and optimization loops for improving agent workflows before and after deployment. |
Full / Explicit | Full / Explicit |
| Specialist automation | ||
|
Browser & Computer Use Browser, desktop, or remote/local computer control for workflows that cannot be handled through stable APIs alone. |
No / Not documented | No / Not documented |
Pricing snapshot
Sourced from the Index pricing dataset · open each vendor's profile for full detail.
| Pricing | ||
|---|---|---|
|
Entry price Lowest public entry point |
Free Starter (1 GB data, 10K scores) · Pro $249/mo | Free tier; Pro about $60/mo plus usage meters; Enterprise custom |
|
Pricing confidence How public the numbers are |
Public — exact | Public — partial |
|
Billing Primary billing axis |
usage | usage meters (storage, ingestion) plus tier |
|
Variable cost Workload / overage exposure |
Medium variable cost | Medium variable cost |
|
Free tier / trial Try before you buy |
Free tier
|
Free tierTrial
|
|
Buying motion Self-serve vs sales call |
Mixed | Mixed |
Choose Braintrust if
- Evaluation driven development is the center of your LLM workflow.
- Bring your own cloud or self hosted deployment is a security requirement.
- Predictable plan pricing with clear overage beats fine grained usage meters.
Choose W&B Weave if
- Your team already runs experiments in Weights and Biases, so tracing lands in one place.
- A low entry price around 60 dollars a month fits a small team budget.
- You want LLM observability connected to broader model training workflows.
Weights and Biases was acquired by CoreWeave in 2025; Weave continues to operate as part of the CoreWeave portfolio. Trace ingestion overage at ten cents a megabyte is the main budgeting variable to model.