validate-milestone

What It Does

validate-milestone sits between all-slices-complete and milestone-completion as an explicit quality gate. Its job is not to re-execute work, but to audit what was delivered against what was promised. For every success criterion in the milestone roadmap, it checks whether the slice summaries and UAT results provide evidence that the criterion was actually met. For every slice, it checks whether the demo/deliverable claim in the roadmap matches what the slice summary reports. It also verifies cross-slice integration points — confirming that boundary map produces/consumes entries align with what was actually built. A fourth check ensures requirement coverage: every active requirement must be addressed by at least one slice.

The validator’s verdict determines what happens next. A pass verdict means all criteria are met, all slices delivered, and no integration gaps exist — the pipeline advances to complete-milestone. A needs-attention verdict means minor gaps exist that do not block completion but should be documented. A needs-remediation verdict means material gaps were found — the validator adds new remediation slices directly to the roadmap file, those slices are planned and executed, and then validation re-runs as a new remediation round.

This prompt is designed to catch the failure mode where individual tasks and slices all pass their own verification but the assembled milestone as a whole does not deliver its promised user-facing capability. All context (roadmap, slice summaries, UAT results, requirements, decisions, and project context) is preloaded inline so the validator can start working immediately without re-reading files.

Results are written directly to {{validationPath}} (typically VALIDATION.md). The report includes a success criteria checklist, a slice delivery audit table, cross-slice integration findings, requirement coverage check, verdict rationale, and — if the verdict is needs-remediation — a remediation plan listing the new slices to be added to the roadmap.

Pipeline Position

This prompt fires after all planned slices are complete. The remediationRound variable tracks how many validation cycles have run — on the first pass it is 0, and it increments with each needs-remediation verdict. When remediation slices are needed, the validator appends them to the roadmap with unchecked [ ] status so they are picked up by the dispatcher in the next execution wave.

Variables

Variable	Description	Required
milestoneId	Current milestone identifier being validated	Yes
milestoneTitle	Human-readable title of the milestone being validated	Yes
workingDirectory	Absolute path to the project working directory	Yes
remediationRound	Current remediation attempt number — 0 on first pass, increments with each needs-remediation cycle	Yes
inlinedContext	Pre-assembled context block containing the roadmap, all slice summaries, UAT results, requirements, decisions, and project context	Yes
roadmapPath	File path to the project roadmap, used for cross-referencing success criteria and appending remediation slices	Yes
validationPath	File path where the validation report should be written (e.g. VALIDATION.md)	Yes

Used By

• /gsd auto — dispatched after all planned slices are complete, in the validating-milestone phase