signal.

Agentic coding and persistent returns to expertise

This report provides evidence on how Claude Code is used in practice, based on a privacy-preserving analysis of around 400,000 interactive sessions from around 235,000 people between October 2025 and April 2026. The share of GitHub projects with coding agent activity has more than doubled since late 2025, 1 and Claude Code users now spend an average of 20 hours per week using the tool. It builds on prior work focused on measures of autonomy in Claude Code sessions, and how Claude Code is changing work at Anthropic .

Agentic coding has taken off. The share of GitHub projects with coding agent activity has more than doubled since late 2025, 1 and Claude Code users now spend an average of 20 hours per week using the tool. 2 Can people without formal coding experience successfully direct an agent through complex technical work? And what will rapid adoption and improvement of these tools mean for knowledge work broadly? While we don’t have full answers to these questions yet, we look to Claude Code usage data for early signals.

This report provides evidence on how Claude Code is used in practice, based on a privacy-preserving analysis of ~400,000 interactive sessions from ~235,000 people between October 2025 and April 2026. It builds on prior work focused on measures of autonomy in Claude Code sessions, and how Claude Code is changing work at Anthropic . 3 Here, we introduce a framework for describing interactive AI coding-assistant usage: what kind of work is being done, who is doing it, and whether it succeeds. We focus on Claude Code usage through a command-line interface (CLI), Claude.ai , or the Claude Code desktop app. 4 By tracking how agentic coding usage changes as models get more capable, we can better understand how these tools affect the labor market for coding professionals and knowledge workers.

What happens on Claude Code may be a preview of where knowledge work is headed, as agents become embedded in non-coding work. We find that Claude is handling more complex and more valuable tasks. At the same time, there remains a clear division of labor in agentic coding: People decide what to build, and the agent decides how to build it.

We also see evidence that domain expertise, and not coding proficiency, amplifies effective use of the tool. In particular, domain experts succeed more often, and more easily recover from errors and misunderstandings. However, the gap between experts and intermediates is modest—suggesting that proficiency in a domain is enough to use the tool almost as effectively as those with deep mastery.

These findings give us an early read on possible transitions in the labor market. In our data, success is determined by how well a person understands the problem they are trying to solve, not whether they’re trained in coding. If these patterns hold across the economy, it suggests that while agentic coding tools may be absorbing some implementation-heavy work, they are also rewarding those with firm understanding of the problems they solve on the job. Coding agents are not substituting for domain expertise—the more understanding a worker brings to an agent, the more quality work the agent is able to do.

To understand what people are using Claude Code for, we classify each session into one of nine work modes—the single activity that best describes what the session is trying to accomplish. 5 Four modes involve writing or maintaining code directly: building something new, fixing something broken, testing code, and orchestrating other agents or automated pipelines. Another category is operating software—deploying, configuring, running pipelines, monitoring systems. Two categories are more about working out what to do: understanding how an existing system works, and planning a change before making it. And two take actions unrelated to code, or where code is incidental to the final product: analyzing data, and communicating via presentations and other prose-based documents.

About 56% of sessions consist of writing (25%), fixing (26%), or testing and orchestrating code (5%). Operating software comprises 17%, while 14% of sessions are planning or exploring, and 13% produce analysis or prose (Figure 1).

We classify each session by having a model read its transcript, then using our privacy-preserving analysis tool, we check them against telemetry that's recorded automatically for every session, including whether any lines of code were added or deleted. The two sources have high agreement—for instance, more than 90% of sessions our classifier labeled as creating or modifying code showed code changes in the telemetry. See the Appendix for details.

How autonomous is Claude Code? Capability evaluations suggest the ceiling is high and rising: on benchmarks such as METR's time-horizon evaluations , frontier models can now complete software tasks that would take a person hours, autonomously working through obstacles along the way. But what does usage actually look like in practice? Here, we look at how much steering is done by the person and by Claude in real sessions.

We investigate this question from two angles. First, we focus on the extent to which people are entrusting decisions to Claude, and second we look at how many actions they give to Claude. To understand the division of decision-making in a session, we build a privacy-preserving decision attribution classifier based on the content of a session. We ask a classifier to list all the meaningful decisions in a session. We separate these decisions into planning (what to do, which approach to take, what counts as done) and execution (which files to change, what code to write, what language to write in, which commands to run). The classifier then attributes each decision to Claude or to the user, giving every session two numbers: the user's share of planning decisions and the user's share of execution decisions.

On average, people make about 70% of the planning decisions but only 20% of the execution decisions (Figure 2). In practice, there is a clear division of labor in agentic coding––people decide what to build, and the agent decides how to build it.

To understand the delegation of actions in a session, we look at the session’s structure instead of its content. A Claude Code session involves Claude and the user going back and forth trading prompts (from the user) and actions (taken by Claude)––the user writes a prompt and Claude goes off and does some work, and then the user writes another prompt, and so forth. In a typical session, there are about four such turns. In our historical data from October to April, each prompt the user sends sets off a chain of around 10 actions taken by Claude on average––and sometimes over 100. 6 In each turn, Claude reads files, edits code, runs commands, and writes on average 2,400 words of output.

How much Claude does between check-ins largely tracks who is making the decisions. When the user keeps control of execution (i.e. makes over 80% of execution decisions), Claude takes fewer actions per turn (about eight actions). And when Claude takes control of planning (i.e. makes over 80% of planning decisions), it takes on the highest number of actions (about 16).

From each transcript, Claude rates the user's apparent expertise at the task on a five-point scale from novice to expert. The expertise classifier looks for three signals: how precisely the user frames their directions, what they ask Claude to verify, and whether the user tends to correct Claude or Claude tends to correct the user. Note that expertise is capturing something quite different from job title or general ability, and, crucially, it is task-specific . A senior engineer asking their first Rust question is a beginner at Rust. An accountant who has never used Python, but tells Claude exactly which reconciliation rules a Python script must enforce and catches the edge case it mishandles at month-end close, is an expert at that task.

The table below shows how we defined each expertise level in the classifier along with an example request from a public dataset of coding agent sessions, SWE-chat . The conversation categorized as Novice gives generic instructions with no implied domain-specific knowledge. The Expert conversation conveys deep knowledge of the codebase and technical environment.

We quantify how expertise relates to Claude’s output and activity per prompt. In typical novice sessions, each prompt sets off about five Claude actions and roughly 600 words of output, while expert sessions set off action chains more than twice as long (12 actions) carrying five times the output (3,200 words) (Figure 3). This gap between novice and expert sessions appears within every kind of work and every band of task value.

These measures complement the autonomy measures in our prior report on Claude Code , which tracked how long the agent runs and how often people approve its actions automatically. Our decision attribution measure, by contrast, captures who makes the substantive decisions in a session as a whole, while our measures of output and actions per prompt measure how much autonomous activity from Claude each human prompt sets off.

To understand who is doing this work, we infer each user's occupation from the session transcript, mapping it to one of 23 major groups in the Bureau of Labor Statistics’ Standard Occupational Classification (SOC) taxonomy. The classifier is instructed to rely only on signals such as the project context the agent loads at the start of a session, the names and structure of their files, any artifacts they reference (e.g., legal filings, clinical data, financial reports, a curriculum, etc.) and vocabulary they use. 7 It is explicitly instructed not to treat the act of coding as evidence of a coding profession. A session is classified into the coding SOC code (Computer and Mathematical Occupations) only when there is clear signal that software or data work is the user’s job. A session in which a lawyer builds a script to automatically flag missing clauses across a folder of contracts is mapped into Legal Occupations, even if the session’s work is primarily software. The session is left unclassified when there is no signal about the user’s occupation.

We were able to infer occupation in about 70% of sessions. Within this set, Computer and Mathematical Occupations, a category which encompasses most software-related jobs, is unsurprisingly the largest group. The next largest are Business and Financial Operations; Arts, Design, and Media; Management; and Life, Physical, and Social Sciences. The fastest-growing non-software occupation groups in our sample are management, sales, and legal occupations.

The composition of the work done with Claude Code changed substantially between October 2025 and April 2026. The clearest change is that the share of sessions spent fixing broken code fell from 33% to 19% (Figure 4). In its place, we saw a greater share of the work that surrounds code. Operating software grew from 14% to 21% of sessions. Writing and data analysis roughly doubled, from about 10% to 20% of sessions.

The tasks themselves also grew more valuable. We approximate each session's economic value by asking what the work would cost on a freelance marketplace, calibrated against a public dataset of real postings. By this measure, the estimated value of the average session rose by 27% between October and April. The rise holds across many kinds of work. Building, operating, and fixing-type tasks all grew more valuable by roughly a third or more (about 43%, 34%, and 32% respectively). These price estimates are coarse, so we use them primarily to compare tasks to one another over time, not as dollar values to be read literally. 8 For details about the construction of the task estimator, see the Appendix .

The estimated value of a task is one way to get a sense of how Claude Code is helping people do their work. Another angle is to look at how many sessions are successful, and what characteristics of a session are linked to success. Across all our measures of success, we see a clear pattern: the more expertise a person exhibits in a session, the higher the likelihood of success. Most of the gain is concentrated at the lower end of the expertise scale––the gap between novice sessions and intermediate sessions is bigger than the gap between intermediate and expert.

Why it matters

This report provides evidence on how Claude Code is used in practice, based on a privacy-preserving analysis of around 400,000 interactive sessions from around 235,000 people between October 2025 and April 2026 Reported by Anthropic Research on June 16, 2026.

Topic dossiers Anthropic & Claude