transfer-reconciliation

name	transfer-reconciliation
description	Lightweight post-transfer reconciliation example — verify tool-reported row count parity and run a small target-side sanity check without re-scanning the source.
tags	["data-engineering","migration","validation","reconciliation"]
version	1.0.0
user_invocable	false
disable_model_invocation	false
allowed_agents	["gen_job"]
kind	validator
severity	blocking
mode	llm
targets	[{"type":"transfer"}]

Transfer Reconciliation

Use this skill at the end of a transfer_query_result run. It is intentionally lightweight: the built-in layer already compares tool-reported source and target row counts, so this skill only demonstrates a small target-side sanity check. Project-specific or strict source-vs-target checks should live in a project/user validator skill.

When this skill fires

ValidationHook triggers this skill automatically at the end of any gen_job agent run that produced one or more TransferTarget deliverables. When the run stayed intra-database (no transfer_query_result calls), this skill is not invoked.

You never call this skill directly. The hook starts a read-only sub-agent whose only job is to execute the checks below against the run's transfer targets and emit a structured JSON report.

What you receive

The hook hands you a SessionTarget containing one or more TransferTarget records. Each record carries only:

• source.name — the source connector key (route execute_sql here for source-side probes only when a project-specific validator explicitly needs them).
• target.datasource / target.database / target.db_schema / target.table — the target coordinates.
• source_row_count, transferred_row_count — tool-reported counts (authoritative for check 1).

Default validator behavior must avoid expensive source re-scans. Do not infer or search for the original source table; many transfers are derived queries, joins, or aggregations. Treat source_row_count / transferred_row_count as the source-side evidence.

Core workflow

For every TransferTarget in the session, run only these example checks:

1. Row count parity — report whether tool-reported source_row_count and transferred_row_count match. This should normally already be present in the precheck context from the built-in layer; summarize it instead of querying the source.
2. Target row count — run one target-side COUNT(*) query using TransferTarget.target.datasource and the target table coordinate. Compare it with transferred_row_count.