You are building developer-productivity tools using the Claude Agent SDK.

Option A begins with the strongest available discriminator: the exact production error text. Anthropic’s tools reference specifies that Grep searches file contents and returns matching lines, enabling the agent to locate a literal error constant or message without loading the full repository. Searching both the stable code SYNC_CONFLICT and the distinctive phrase protects against cases where the identifier and displayed message are defined separately. The agent can then read only the matching files and follow the surrounding call path, error construction, and service ownership. Option B assumes that errors are stored in conventionally named directories, which may not hold in a twelve-service repository. Option C consumes substantial context before using the most direct evidence. Option D narrows the search to consumers of a known shared error module, but the message may be locally defined, generated from configuration, or wrapped by another component. Grep followed by targeted Read operations follows Anthropic’s broader context-engineering principle of retrieving relevant source material just in time instead of placing an entire codebase into the active context.

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