Local AI Coding Tools Need Defined Boundaries, Not Just Local Execution

Running an AI coding agent locally reduces data exposure but does not itself constitute a security model, according to a developer-focused analysis. A locally executed process can still read broad file systems, inherit shell credentials, and reach external services, making execution location just one deployment property among many. Security reviewers are advised to explicitly define readable files, writable files, permitted commands, and allowed external systems before starting any agent session. Secrets should be kept out of prompts and transcripts, with credentials managed through scoped stores that separate read and write authority. Effective local-first security requires three aligned conditions: data remaining in appropriate locations, narrowly scoped authority, and sufficient evidence provided to human reviewers before changes are approved.