Capability · Framework — observability

Humanloop

Humanloop is the PM-and-engineer collaboration layer for LLM apps: prompts live as first-class versioned resources, evaluations can be automatic or human-run, and logs tie back to the prompts that produced them. Teams use it as the single source of truth for prompts so that product managers can iterate without a deploy.

Framework facts

Category: observability
Language: Python / TypeScript
License: Commercial SaaS (SDK open-source)
Repository: https://github.com/humanloop/humanloop-python

Install

pip install humanloop

Quickstart

from humanloop import Humanloop

hl = Humanloop(api_key='hl-...')

resp = hl.prompts.call(
    path='my-app/chat',
    inputs={'question': 'what is AGI?'}
)
print(resp.logs[0].output)

Alternatives

LangSmith — LangChain-native
Braintrust — prompt management + evals
PromptLayer — prompt registry focused
W&B Weave — eval-heavy alternative

Frequently asked questions

Is Humanloop open-source?

No — the platform is hosted SaaS (with private-cloud options). The client SDKs are Apache-2.0 on GitHub.

Why separate prompts from code?

So non-engineers can iterate. Humanloop lets product and domain experts edit prompts in a UI with versioning and approvals, while engineers call them by path/ID from production code.

Sources

Humanloop — docs — accessed 2026-04-20
Humanloop SDK GitHub — accessed 2026-04-20