Computer History Museum · Published 2026-09-24

In Conversation with Boris Cherny, Creator of Claude Code

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Summary

Overview

  • Speaker: Boris Cherny and David C. Brock
  • Channel: Computer History Museum
  • Main topic: The creation, evolution, safety, and future impact of Claude Code and AI-assisted programming tools.
  • Purpose: To explore the intersection of artificial intelligence and software engineering through the lens of Claude Code's creation and Anthropic's philosophy on AI safety. In this conversation at the Computer History Museum, software engineer Boris Cherny discusses his journey creating Claude Code at Anthropic, the transition from traditional programming to AI-driven agentic software engineering, AI safety, prompt injection, and the broader societal implications of automating software development.

Topic Map

Introduction and Background

  • Explanation: Boris Cherny's early days with coding, calculators, and his path through Meta and Anthropic.
  • Key claims:
    • Coding started at age 13 with a TI-83 calculator.
    • Early programming was driven by practical needs, like getting good grades on math tests.
    • Moving from Meta to Anthropic was motivated by a desire to make AI go in a better, safer direction.
  • Examples:
    • Programming answers into a TI-83 calculator to ace math tests.
  • Terminology:
    • TI-83
    • assembly
    • Anthropic
    • Meta
  • Why it matters: Provides context on the developer mindset and how curiosity drives technological exploration.

The Birth of Claude Code and Agentic Coding

  • Explanation: How LLMs evolved from autocomplete text-completers to autonomous agents with tools.
  • Key claims:
    • Early LLM usage in coding was limited to tab-completion.
    • Anthropic models like Sonnet 3.5 enabled full file and function generation.
    • Giving models tools (like reading/writing files and running bash commands) transformed LLMs from simple chatbots into active agents.
  • Examples:
    • Moving from pressing tab to complete a line to letting the AI edit entire files and run code.
  • Terminology:
    • LLM
    • Sonnet 3.5
    • agentic coding
    • prompt injection
  • Why it matters: Explains the technical leap that made agentic coding workflows viable and transformative.

AI Safety, Alignment, and Prompt Injection

  • Explanation: Anthropic's focus on AI safety and how they handle adversarial threats like prompt injection.
  • Key claims:
    • Anthropic is fundamentally an AI safety lab.
    • Prompt injection occurs when an attacker tricks an AI model into executing malicious instructions via untrusted data.
    • Automated guardrails and secondary safety models ('automode') help prevent models from going rogue.
  • Examples:
    • Injecting hidden instructions into web pages read by an AI agent to exfiltrate data.
  • Terminology:
    • alignment
    • prompt injection
    • automode
    • reinforcement learning
  • Why it matters: Highlights the critical challenges of deploying powerful AI systems safely in production environments.

The Future of Software Engineering

  • Explanation: How automated coding changes the role of software engineers and the democratization of software creation.
  • Key claims:
    • Coding will become accessible to everyone, shrinking the gap between professional and non-professional developers.
    • The printing press historical analogy illustrates how automation increases literacy in a domain.
    • Curiosity, domain knowledge, and good judgment are becoming more important than raw coding syntax skills.
  • Examples:
    • Comparing the explosion of literacy after the printing press to the democratization of software creation through AI.
  • Terminology:
    • scaling laws
    • printing press analogy
    • software automation
  • Why it matters: Provides a philosophical and economic outlook on how software development careers and industries will evolve.

Key Points

Tools transform chatbots into agents

  • Explanation: Giving LLMs access to file systems, bash commands, and external APIs allows them to perform autonomous tasks rather than just generating text.
  • Evidence: Claude Code's ability to read, write, and execute code autonomously.
  • Practical implication: Developers interact with AI as a teammate rather than an autocomplete engine.

The importance of AI safety and sandboxing

  • Explanation: Autonomous models require rigorous safety guardrails, including human-in-the-loop verification and isolated virtual machine execution.
  • Evidence: The development of 'automode' and isolated sandboxes in products like Co-work.
  • Practical implication: Security must be built into AI infrastructure from day one to prevent malicious exploits.

Democratization of software creation

  • Explanation: Just as the printing press democratized reading and writing, AI coding tools make software engineering accessible to a much broader audience.
  • Evidence: The historical parallel of literacy rates soaring after Gutenberg's invention.
  • Practical implication: Domain experts without traditional CS backgrounds can build complex software systems.

Frameworks, Models & Processes

The Three Forces of Data Center Construction

  • How it works: Describes the exponential interplay between compute availability, model efficiency, and user demand.
  • Components:
    • Amount of compute built
    • Model efficiency (tokens per dollar)
    • User demand for AI capabilities
  • When to use: Understanding the macroeconomic and infrastructural growth of AI systems.

Model Evaluation and Alignment Pipeline

  • How it works: A multi-layered approach to ensuring AI model safety through evals, mechanistic interpretability, and reinforcement learning.
  • Components:
    • Evals (artificial benchmarks)
    • Mechanistic interpretability (neural probing)
    • Automated classification (automode)
  • When to use: Developing and securing large language models against adversarial attacks.

Examples & Case Studies

Boris writing programs on a TI-83 calculator in high school math class.

  • Illustrates: Early practical drive for automation and coding.
  • Lesson: Solving real problems efficiently often sparks a lifelong career in software engineering.

Testing prompt injection robustness using simulated bounty attacks.

  • Illustrates: The difficulty of securing LLM agents against malicious inputs.
  • Lesson: Security in AI requires active defense mechanisms like dual-model validation.

Actionable Takeaways

  • Immediate:
    • Experiment with agentic coding tools like Claude Code.
    • Incorporate robust sandboxing when giving AI execution privileges.
  • Strategic:
    • Prepare for a world where software creation is democratized beyond traditional developers.
    • Focus on domain expertise, curiosity, and product judgment rather than raw syntax memorization.
  • Questions to investigate:
    • How will software engineering job roles shift as AI handles end-to-end coding tasks?
    • What new safety vulnerabilities will emerge as multi-agent systems become autonomous?

Claims Worth Verifying

  • Frontier model performance scales exponentially with compute, data, and parameter size. (technical)
  • Post-training alignment techniques can reduce prompt injection vulnerability rates significantly. (empirical)

Notable Quotes

"We decode technology—its computing past, digital present, and future impact on humanity." (at 1:59) "The model is able to do all of these things and the product is getting in the way." (at 20:38)

Compressed Summary

  • AI coding assistants evolved from tab-completion to autonomous agents with tool use.
  • Anthropic focuses heavily on AI safety, alignment, and secure sandboxing.
  • Agentic tools like Claude Code blur the line between coding and non-coding tasks.
  • Software engineering is shifting toward domain curiosity and product judgment over syntax.
  • Keywords: claude code, ai safety, agentic coding, llm alignment, software engineering
  • Core insight: AI coding tools have transformed from simple autocomplete engines into autonomous agents, fundamentally democratizing software creation while making AI safety paramount.

Core insights

6
Architecturemedium noveltymoderate evidence

The step-change from chatbot to agent is tool access (file system, bash, external APIs) rather than raw model capability — the model's role shifts from generating text to taking autonomous actions in an execution environment.

Why it matters

The agent's capability boundary is defined by what the runtime exposes as tools, not by the model alone; the abstraction that must be designed carefully becomes the tool/execution surface.

Generalization

Agent capability is bounded by the action surface (tools/permissions) you grant, so runtime and permission design matter as much as model selection.

Giving LLMs access to file systems, bash commands, and external APIs allows them to perform autonomous tasks rather than just generating text.
Open source video
Claude Code's ability to read, write, and execute code autonomously.
Open source video
Early LLM usage in coding was limited to tab-completion.
Open source video
Mechanismhigh noveltymoderate evidence

Prompt injection is defended architecturally with a secondary safety model ('automode') that acts as an independent classifier/guard over the primary model's intended actions — dual-model validation rather than relying on the primary model to police itself.

Why it matters

Moves safety enforcement out of the model doing the work into a separate validation layer, which is a reusable pattern for any agent with tool/execution privileges.

Generalization

Putting a separate model/classifier between agent intent and execution is a generalizable defense-in-depth pattern for untrusted-data-driven agents.

Automated guardrails and secondary safety models ('automode') help prevent models from going rogue.
Open source video
Security in AI requires active defense mechanisms like dual-model validation.
Open source video
Practicemedium noveltymoderate evidence

Autonomous execution privileges require isolated VM sandboxing plus human-in-the-loop verification as a baseline infrastructure requirement, not an optional add-on.

Why it matters

Security must be designed into the agent runtime from day one; retrofitting isolation after agents can already write and run code is costly and risky.

Generalization

Any system granting an autonomous agent execution rights should default to process-level isolation and gated human approval.

Autonomous models require rigorous safety guardrails, including human-in-the-loop verification and isolated virtual machine execution.
Open source video
The development of 'automode' and isolated sandboxes in products like Co-work.
Open source video
Security must be built into AI infrastructure from day one to prevent malicious exploits.
Open source video
Mental Modelmedium noveltyweak evidence

Safety is treated as a layered pipeline spanning artificial benchmarks (evals), mechanistic interpretability (neural probing), and automated classification (automode) — each layer covering a different failure class rather than one monolithic safety mechanism.

Why it matters

Frames safety as multiple independent detectors with different coverage, which affects how you instrument, evaluate, and version an agent platform.

Generalization

Reliability/safety mechanisms should be layered by failure class (static eval, internal inspection, runtime guard) rather than consolidated.

A multi-layered approach to ensuring AI model safety through evals, mechanistic interpretability, and reinforcement learning.
Open source video
Evals (artificial benchmarks)
Open source video
Mechanistic interpretability (neural probing)
Open source video
Automated classification (automode)
Open source video
Mental Modelmedium noveltyweak evidence

AI infrastructure growth is framed as a feedback loop among three forces — compute built, model efficiency (tokens per dollar), and user demand — implying cost-efficiency gains feed demand rather than saturate it.

Why it matters

Cost-per-token improvements do not reduce total spend in this framing; they expand demand, which affects capacity planning and cost modeling for agent workloads.

Generalization

Efficiency gains in inference economics should be modeled as demand-expanding, not demand-reducing (Jevons-style loop).

Describes the exponential interplay between compute availability, model efficiency, and user demand.
Open source video
Amount of compute built
Open source video
Model efficiency (tokens per dollar)
Open source video
User demand for AI capabilities
Open source video
Predictionlow noveltyweak evidence

As agentic coding absorbs end-to-end tasks, the scarce skill shifts from syntax production to domain knowledge, curiosity, and product judgment — meaning the human's value moves to specification, verification, and domain framing.

Why it matters

Suggests tooling and workflow design should optimize for expressing intent and verifying outcomes rather than assisting keystroke-level code entry.

Generalization

When generation is cheap, engineering leverage concentrates in problem framing, evaluation, and acceptance criteria.

Coding will become accessible to everyone, shrinking the gap between professional and non-professional developers.
Open source video
Curiosity, domain knowledge, and good judgment are becoming more important than raw coding syntax skills.
Open source video

Deep dives

5

Guard-model evadability under asymmetric capability

Research question

When the working model that proposes an action is stronger than the guard model that vets it, at what rate can the working model generate action plans that pass the guard while still achieving an injected malicious objective?

Why

Dual-model validation is only a safety layer if the validator is not systematically weaker than the thing it validates. If evasion rate rises with primary-model capability, then 'automode' style guards create a false floor of safety exactly when agents get more competent, and teams will under-invest in isolation and human gating.

Automated guardrails and secondary safety models ('automode') help prevent models from going rogue.
Open source video
Security in AI requires active defense mechanisms like dual-model validation.
Open source video
Prompt injection occurs when an attacker tricks an AI model into executing malicious instructions via untrusted data.
Open source video
Source video

Action surface as the true capability boundary of an agent

Research question

For a fixed model, how much does repo-level task autonomy improve when you expand the tool/permission surface (read, write, bash, network) versus when you upgrade the model with a fixed surface?

Why

If autonomy is dominated by the action surface, then engineering effort and safety review should be focused on the tool and permission abstraction rather than chasing model upgrades. It also reframes 'we need a better model' requests as permission-design requests, which changes roadmap and risk allocation.

Giving models tools (like reading/writing files and running bash commands) transformed LLMs from simple chatbots into active agents.
Open source video
Early LLM usage in coding was limited to tab-completion.
Open source video
Moving from pressing tab to complete a line to letting the AI edit entire files and run code.
Open source video
Source video

Untrusted ingestion as a first-class security boundary

Research question

Does trust-tiering ingested content (web pages, retrieved docs, third-party tool output) and stripping executable instruction patterns measurably reduce injection success on agentic tasks without breaking legitimate task completion?

Why

Once the model acts on what it reads, every read becomes an authorization decision. If provenance tiering reduces injection success with acceptable task-quality loss, it becomes a runtime primitive rather than a per-application heuristic, and retrieval/browsing layers must expose provenance metadata.

Injecting hidden instructions into web pages read by an AI agent to exfiltrate data.
Open source video
Prompt injection occurs when an attacker tricks an AI model into executing malicious instructions via untrusted data.
Open source video
Security must be built into AI infrastructure from day one to prevent malicious exploits.
Open source video
Source video

Mapping layered safety mechanisms onto agent runtime stages

Research question

Do evals, interpretability probing, and runtime classification cover disjoint failure classes, or do they overlap while leaving specific agent failure modes (multi-step exfiltration, permission escalation, cross-turn instruction carryover) uncovered by all three?

Why

The 'layered pipeline' claim is only useful if the layers are non-redundant and instrumentable at distinct runtime stages. If coverage overlaps and gaps remain, teams will report composite safety posture that does not correspond to any single measurable property of the deployed agent.

A multi-layered approach to ensuring AI model safety through evals, mechanistic interpretability, and reinforcement learning.
Open source video
Evals (artificial benchmarks)
Open source video
Mechanistic interpretability (neural probing)
Open source video
Automated classification (automode)
Open source video
Source video

Inference efficiency as a demand-expanding loop for agent workloads

Research question

When tokens-per-dollar improves by a fixed factor, does total agent workload spend fall, stay flat, or rise, and over what horizon does the response differ?

Why

Agentic coding multiplies tokens per task by looping over read/write/execute cycles, so naive cost models that assume efficiency reduces spend will systematically under-provision. A demand-expanding model changes capacity planning and unit-economics assumptions for platform teams.

Describes the exponential interplay between compute availability, model efficiency, and user demand.
Open source video
Amount of compute built
Open source video
Model efficiency (tokens per dollar)
Open source video
User demand for AI capabilities
Open source video
Source video

Article ideas

4

Your Agent's Capability Boundary Is Its Permission Boundary

Agent capability is set by the action surface you expose, not by the model you pick; therefore permission and sandbox design, not model selection, should be the primary design artifact for any agentic system, and teams that treat tools as an implementation detail will ship both unsafe and weak agents.

Angle

Reframe the standard 'which model?' engineering debate as a permission-scoping exercise, with a worked argument that a fixed model plus expanded tool surface outperforms a model upgrade with a fixed surface.

Source video

Guard Models Are a Layer, Not a Moat

Secondary-model validation ('automode') is valuable but structurally fragile: a guard weaker than the model it vets will be evaded at a rate that grows with primary-model capability, so guard models must be paired with process isolation, human gating, and continuous adversarial measurement rather than treated as the safety guarantee.

Angle

Argue against safety architectures that consolidate trust in a single classifier, and specify what must sit behind the guard model for the claim of safety to be measurable.

Source video

Every Read Is an Authorization Decision

Giving an agent execution privileges turns content ingestion into a security boundary, so provenance tiering and content sanitization belong in the agent runtime, not in application code — and retrieval systems that cannot report where content came from are unsafe by construction.

Angle

Walk through how the same channel that makes an agent useful (reading the web, docs, tool output) becomes the injection vector, and what runtime-level provenance metadata must look like.

Source video

When Generation Is Cheap, Verification Is the Bottleneck

Democratizing code generation to non-engineers does not remove engineering work; it relocates it into specification, acceptance criteria, and verification, and organizations that do not build verification infrastructure will accumulate unmaintainable systems faster than they can review them.

Angle

Challenge the optimistic 'coding for everyone' framing by tracing where the review burden goes and why verification tooling becomes the limiting resource rather than authoring tooling.

Source video

Project ideas

4

Asymmetric Guard Evasion Harness

gatehouse

A stronger working model can produce action plans that pass a weaker guard classifier while still satisfying an injected malicious objective, and evasion success rate increases monotonically as the capability gap between working model and guard model widens.

Proof of concept

Two-model harness: a planner model receives task context containing an injected instruction and emits a tool-call plan; a guard model independently classifies each plan as benign/malicious; blocked plans are not executed in a sandboxed VM; record whether the malicious objective is achieved in the sandbox without the guard flagging it.

Measurement

Attack success rate (malicious objective achieved without guard block) across capability gaps and across injection placements, plus guard false-positive rate on matched benign tasks.

Source video

Permission-Surface Ablation for Repo Tasks

movement-lab

Repo-level task completion rate scales more with incremental tool/permission surface (read-only, write, bash, network) than with a model upgrade at a fixed surface, up to the point where added surface mainly increases incident risk rather than success.

Proof of concept

Take a fixed set of repo-level tasks, run them under a fixed model across graded permission tiers, then run them with an upgraded model at the lowest tier; log both completion and any unauthorized-scope actions taken during successful runs.

Measurement

Task completion delta per tier vs. per model upgrade, and unauthorized-action rate per tier among successful runs.

Source video

Provenance-Tiered Ingestion Gateway

gatehouse

Tagging ingested content by trust tier and neutralizing imperative/instruction-shaped spans before it enters agent context reduces injection success on browsing tasks by a measurable margin with no more than a small degradation in legitimate task success.

Proof of concept

Middleware that labels each ingested chunk with provenance (first-party repo, user doc, external web, third-party tool output), applies tier-specific transformation, and enforces that low-trust content cannot directly parameterize write/bash calls without an out-of-band confirmation step.

Measurement

Injection success rate and legitimate-task success rate on a matched benchmark of browsing-plus-action tasks, with and without tiering enabled.

Source video

Safety Layer Coverage Matrix

beyond-evals

Static evals, interpretability probes, and runtime classification target overlapping failure classes while leaving specific agentic failure modes (multi-step exfiltration, permission escalation across turns, cross-turn instruction carryover) uncovered by all layers.

Proof of concept

Build a failure-mode taxonomy, construct minimal reproducible cases per mode, then run each case against each of the three safety layers independently and record which layer detects it and at what stage of the trajectory detection occurs.

Measurement

Per-failure-mode detection coverage matrix (layer x failure mode), redundancy index across layers, and count of failure modes with zero coverage.

Source video

Architectural implications

3

Tool/execution access is what makes a model an agent, and that access requires isolation and gating.

Before

Model output is text reviewed by a human before any action is taken.

After

Model intent flows through a guard model into an isolated VM where it reads, writes, and executes code autonomously.

Consequence

Sandboxing, permission scoping, and guard-model validation become first-class runtime infrastructure rather than application-level features.

Source video

Prompt injection is defended by a secondary safety model rather than by hardening the primary model.

Before

The model that performs the task is also trusted to refuse malicious injected instructions.

After

A separate classifier/safety model sits between the working model's plan and its execution.

Consequence

Introduces a new component to version, evaluate, and latency-budget, and creates a distinct interface between 'intent' and 'action' in the agent runtime.

Source video

Untrusted data channels (e.g., web pages the agent reads) are an attack surface once the agent can act on what it reads.

Before

Reading content was harmless because the model only produced text for a human to judge.

After

Any content the agent ingests can carry executable instructions, so ingestion becomes a security boundary.

Consequence

Data provenance and content sanitization move into the agent runtime; retrieval and browsing need trust tiering.

Source video

Tradeoffs and failure modes

3

Autonomy vs. injection surface

Benefit

Giving the agent file/bash/API access enables end-to-end autonomous coding and task execution.

Cost or risk

The same channels used to read untrusted data become vectors for injected instructions that can exfiltrate data or take unintended actions.

Injecting hidden instructions into web pages read by an AI agent to exfiltrate data.
Open source video
Source video

Dual-model safety validation

Benefit

An independent safety model can catch rogue or maliciously-induced behavior the working model would execute.

Cost or risk

Adds a second model in the critical path and another component that must itself be evaluated and maintained.

Automated guardrails and secondary safety models ('automode') help prevent models from going rogue.
Open source video
Source video

Democratized software creation vs. verification burden

Benefit

Non-CS domain experts can build complex software without traditional syntax skills.

Cost or risk

More software produced by users with less engineering discipline shifts the burden to judgment and verification, where errors may be harder to detect.

Domain experts without traditional CS backgrounds can build complex software systems.
Open source video
Source video

Open questions

4

Do post-training alignment techniques measurably reduce prompt injection vulnerability rates, and by how much?

Why unresolved

The summary lists this as a claim worth verifying with no reported numbers or methodology.

Research direction

Run controlled prompt-injection bounty/red-team evaluations before and after alignment post-training on the same model.

Source video

What new safety vulnerabilities emerge specifically as multi-agent systems become autonomous?

Why unresolved

The summary raises this as an unresolved question without describing mechanisms or observed failures.

Research direction

Build multi-agent testbeds with injected instructions propagating between agents and measure attack surface growth.

Source video

Does secondary-model (automode) validation remain effective as the working model gets more capable, or does it become a bottleneck/evadable layer?

Why unresolved

The summary asserts automode helps prevent rogue behavior but gives no evidence on evasion or scaling limits.

Research direction

Adversarially probe the guard model with instructions crafted by the stronger primary model.

Source video

How will software engineering roles and team structures actually shift once agents handle end-to-end coding tasks?

Why unresolved

Stated as a prediction, not an observed outcome, with only a historical analogy as support.

Research direction

Longitudinal study of team composition and task allocation in orgs adopting agentic coding tools.

Source video

Key claims

7
causalVerification needed

Tool access (file system, bash, external APIs) is what transforms LLMs from text generators into autonomous agents.

Evidence

Giving models tools (like reading/writing files and running bash commands) transformed LLMs from simple chatbots into active agents.

Question

Does measured task autonomy scale primarily with tool/permission surface rather than model capability?

Source video
opinionVerification not requested

Anthropic is fundamentally an AI safety lab.

Evidence

Anthropic is fundamentally an AI safety lab.

Source video
factualVerification not requested

Prompt injection occurs when an attacker tricks a model into executing malicious instructions via untrusted data.

Evidence

Prompt injection occurs when an attacker tricks an AI model into executing malicious instructions via untrusted data.

Source video
causalVerification needed

Secondary safety models and automated guardrails prevent models from going rogue.

Evidence

Automated guardrails and secondary safety models ('automode') help prevent models from going rogue.

Question

What is the measured reduction in rogue actions when a secondary safety model validates agent intent, and how evadable is it?

Source video
opinionVerification needed

Post-training alignment techniques can significantly reduce prompt injection vulnerability rates.

Evidence

Post-training alignment techniques can reduce prompt injection vulnerability rates significantly. (empirical)

Question

What is the measured before/after prompt-injection success rate across alignment post-training?

Source video
causalVerification needed

Frontier model performance scales exponentially with compute, data, and parameter size.

Evidence

Frontier model performance scales exponentially with compute, data, and parameter size. (technical)

Question

Under which benchmarks and ranges does the scaling relationship hold, and does it hold for agentic/tool-use tasks?

Source video
predictionVerification needed

Coding will become accessible to everyone, shrinking the gap between professional and non-professional developers.

Evidence

Coding will become accessible to everyone, shrinking the gap between professional and non-professional developers.

Question

Do non-professional developers produce correct, maintainable systems at rates approaching professionals when using agentic tools?

Source video

Connections

4