A developer uses Claude Code to refactor a function during a development session.

The key difference is reviewer independence. In the original session, Claude retains the reasoning, assumptions, implementation decisions, and intermediate conclusions that led to the refactor. That context can anchor the subsequent review toward defending or confirming the chosen approach instead of evaluating the resulting code independently. The separate CI review begins with fresh context and can assess the implementation solely against the code and review criteria.

Anthropic’s Claude Code best-practices documentation explicitly states that fresh context improves code review because Claude is not biased toward code it has just written. It recommends a writer/reviewer pattern using separate sessions or a review subagent with an isolated context.

Option B is possible in an uncontrolled comparison, but the scenario’s defining distinction is that one review occurs in the implementation session and the other is independent. Option C is false because local Claude Code can read and search the repository when permissions and tools permit it; it is not inherently restricted to the current file. Option D would require evidence of context saturation, such as degraded instruction following or an almost-full context window. No such evidence is supplied. Prior-reasoning bias most directly explains the observed discrepancy.

================