Contract-Bounded Agents - A Practical Method for Building LLM Agents over Distributed Operational Pipelines

An investigation into why a unit of business work did not finish in a distributed operational pipeline crosses several systems of record: schedulers, orchestration engines, warehouses, code repositories and configuration stores. This monograph formulates Contract-Bounded Agent Design (CBAD), a reproducible engineering method for building language-model agents that conduct such investigations within fixed boundaries and can be carried from one pipeline to the next. The method rests on four structural decisions: one narrow, read-only tool per external source, whose description serves as a semantic contract; safety contracts enforced in code, including statement guards, pinned query scopes, payload ceilings and truncation reported with true totals; an explicit failure taxonomy that classifies by meaning on two orthogonal axes, the business stage at which work stopped and the concern that owns the fix; and a named separation between the current state of the work and its historical occurrence. Around the decisions the book sets an ordered investigation runbook, an answer discipline that limits each answer to what the tools returned, and four named design rules: liveness check before trust, best-effort secondary write, partial success by construction and routing by identifier shape. The decisions were derived from two systems developed separately in the author’s own practice as a software engineer, an incident-investigation agent over a workflow orchestration engine and a multi-purpose assistant over a scheduled data pipeline, and the graded convergence of their designs is the principal evidence for the method. The method is positioned against research on tool-using agents, AIOps and failure management, natural-language interfaces to data, software architecture and technical debt. Its procedures are given as checklists, decision tables and rule cards, worked through on a constructed claims-processing pipeline, and the final chapter adds a transfer checklist and a staged adoption path. The book addresses software engineers, site reliability engineers and architects who build, review or adopt agents over production workflow and data systems.