All capabilities
Every capability is one POST to https://api.milliseconds.ai, with text or texts in the body. Every request needs an API key. See Authentication.
The eight capabilities
Latencies are wall-clock measurements from a laptop on 2026-09-18, median of 7 runs, over short inputs of 51 to 199 characters. They include TLS and internet transit. Every single-pass call lands near 0.4 s; the model itself takes 36 to 54 ms of that. classify-tree repeats one classifier call per level, so its latency is the sum of its levels. How it works names the two models and gives the measured capacity table.
The routing rules
- You need a true or false verdict on one claim: use yes-no.
- You need exactly one label from a fixed set: use classify.
- Your labels form a tree and you need the whole path: use classify-tree.
- You need an ordered level, such as severity or sentiment: use rate.
- You need a value that the text states, with its offsets: use answer for one question. Use extract for a whole record, or entities for every occurrence.
- You already hold a value and must check it against the text: use verify.
Choosing a capability works through the near-miss pairs, such as yes-no against classify with two labels.
What every capability shares
Each capability response carries three headers: x-input-chars, the number of input characters, x-input-tokens, the input tokens billed for this call, and x-inference-ms, the model processing time for this request. Cost scales with everything you send: the text plus the labels, statements, questions, or schema. See Pricing.
Writing the labels and statements
The label text is what the model reads. "yes" and "no" carry no meaning for it. Write text that describes the case.
A when_true of "yes" with a when_false of "no" measurably flipped a correct yes-no answer to wrong. The probability fell from 1 to 0.004 on the same input. Writing good statements and labels shows the wording that works.
Images
Every capability also reads one image. Send image as base64 instead of text, or with text.
The result keeps the same shape it has on text. See Images.
Try each one
Open the API Reference tab and use the Try it panel on any endpoint page. The panel needs no key and no setup. The Playground guide gives a worked example per capability and names what to read in each response.