Free · no signup · browser-local

Offline Agent Output Evaluator: JSON and Text Assertions

Test existing outputs with equals, contains, JSON validity, JSON equality and Unicode length assertions. Export deterministic results without calling a model.

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Browser-local preparation and checks · no model calls · no input storage

Configure the check

Each case: id (optional), actual (text), assertions (array). Types: equals, contains, not-contains, is-json, json-equals, length (min/max Unicode code points). Text settings affect comparisons and length; JSON checks use original actual text.

Your output

result.json

Complete the input to preview and export your result.

These are local preparation and validation tools. A passing check is limited to the stated rules; services are not called, authenticated or executed.

Getting started

Paste a JSON array of actual outputs and assertions, choose normalization, then run the local checks.

Before you use the result

This does not call models or grade factual quality. It checks equals, contains, not-contains, JSON, JSON equality and text length only.

Try an example

Load the built-in example, change one value and inspect the actual exported result.

How it works

Bounded browser-local parsing and deterministic rules; no model calls, arbitrary code or remote schema fetches.

Frequently asked questions

Check existing model outputs with deterministic assertions, Unicode lengths and normalization settings.

How do I use Agent Output Evaluation Runner?

Paste a JSON array of actual outputs and assertions, choose normalization, then run the local checks.

Does this tool upload my data?

Inputs and files are processed in your browser. Page-view analytics do not contain your tool input.

What should I check before using the result?

This does not call models or grade factual quality. It checks equals, contains, not-contains, JSON, JSON equality and text length only.

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