Neuronify

Tool use (function calling)

Letting a language model call external functions and APIs — search, databases, code execution — by emitting structured requests the application then runs.

Hiring data as of September 20, 2026 · refreshed daily

companies naming it
10 of 47companies naming it
open roles naming it
13open roles naming it
of those based in NYC
9of those based in NYC
pay: under 8 posted ranges
—pay: under 8 posted ranges

What Tool use means

Tool use, also called function calling, is how a language model acts on anything outside its own text. The application describes the available functions; the model responds with a structured request to call one; the application executes it and returns the result for the model to continue with. It is the mechanism underneath every agent.

The craft is in tool design: what each tool is named, how its parameters are described, what it returns on failure. A model can only be as reliable as the tools are legible to it, and a badly described tool produces errors that look like model mistakes.

Tool use in New York job posts

10 of the 47 New York AI companies we track name Tool use in at least one open role today, across 13 postings. 9 of those are based in New York; the rest are remote or in the companies’ other offices.

This is engineering vocabulary: 85% of the postings that name it are Engineering roles.

How to read it

Almost always appears next to AI agents and evals, in postings for engineers building agent platforms. It indicates hands-on agent work rather than chat-interface work. Expect design questions: how you would expose an internal API to a model, and how you would stop it being called in ways you did not intend.

What these roles pay

Not enough data to publish. We need at least eight distinct posted salary ranges on New York roles naming Tool use before showing a median, and today there are fewer. For posted pay by function and seniority across the whole market, use the NYC salary calculator or the NYC AI engineer salary guide.

Trend

We began extracting this term from posting text on September 20, 2026. Job descriptions disappear when a role is filled, so the series cannot be backfilled; a trend line appears here once a week of data exists.

Who names it

Open roles naming Tool use, by company.

  • Normal Computing3
  • Pinecone2
  • AlphaSense1
  • Clay1
  • Headway1
  • Mirage (fka Captions)1
  • Patlytics1
  • Rogo1
  • Sixfold1
  • SmarterDx1

Which roles

The same postings, by function and by seniority.

  • Engineering11
  • Research2
  • Mid8
  • Staff/Principal3
  • Entry1
  • Senior1

Named alongside Tool use

Terms that appear in the same postings far more often than chance would put them there. The number is how many of the 10 companies pair the two.

Open roles naming Tool use

A sample from today’s data, New York roles first and one per company before any repeats. Links go to the employer’s own posting. For the full market, see AI jobs in NYC.

How this is counted

Every day we read the open roles on the public job boards of the New York AI companies in our coverage — the NYC AI 100 and the AI in NYC Show roster. This term is matched against each role’s description after removing the text a company repeats across its postings, so an “About us” paragraph cannot tag every role the company has open. A vendor’s own postings never count toward its own name.

The figure means named in a job posting. It does not mean used in production, and a “nice to have” counts the same as a requirement. Companies are the headline number because posting counts are dominated by whichever few employers are hiring hardest this month.

Full method, including the pay rules, is on the glossary index; the underlying series is the NYC AI Hiring Index.

Tool use — common questions

What does Tool use mean in an AI job posting?

Letting a language model call external functions and APIs — search, databases, code execution — by emitting structured requests the application then runs. Almost always appears next to AI agents and evals, in postings for engineers building agent platforms. It indicates hands-on agent work rather than chat-interface work. Expect design questions: how you would expose an internal API to a model, and how you would stop it being called in ways you did not intend.

How many New York AI companies are hiring for Tool use?

As of September 20, 2026, 10 of the 47 New York AI companies we track name Tool use in the description of at least one open role, across 13 postings (9 based in New York). The count refreshes daily from the companies’ own job boards.

What do roles that ask for Tool use pay in New York?

We do not publish a pay figure for Tool use yet. Fewer than eight New York postings naming it carry a distinct posted salary range, and below that number a median says more about two or three employers than about the market.

Which skills are asked for alongside Tool use?

In the same postings, the terms most distinctively paired with Tool use are LangGraph, Guardrails, Multimodal AI, Vector search, Evals. We rank pairings by how much more often they appear together than apart, so near-universal terms such as Python do not crowd out the informative ones.

Need someone who has actually shipped this?

A keyword in a posting is easy to match and hard to verify. We match companies with AI engineers and consultancies vetted on production work, and tell you when the project needs a different skill than the one you named.

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