The reference library

Everything here describes a published specification, standard or file format rather than this product. Each page names the document it was read from, the edition, and the date it was checked. Where a governing document asserts copyright its requirements are stated in our own words with the clause cited; where it is a United States Government work it is quoted directly.

Nothing on these pages decides a submission, attributes a delay, or states an entitlement. Where the authorities disagree, the disagreement is reported and left standing.

If you need to know what an agency requires

All the agencies, compared side by side — required software, submission deadlines, update frequency, narrative, revision triggers, time impact analysis and float ownership, in two tables. It also states which agencies have not been read, because a comparison that hides its own coverage is worth less than one that admits it.

If you need to know what the specifications require about one thing

The agency pages above answer "what does this agency require". These turn the question round and answer "what do all of them require about one thing" — which is only possible because sixteen specifications have been read here.

• Time impact analysis — who requires one, under what trigger, what it must contain, and the ones that require nothing
• Baseline schedule submission — deadlines, review periods, and what is withheld while a baseline is outstanding
• Recovery schedules — the delay thresholds that put a contractor into recovery, and who decides
• Schedule narrative — what each agency requires a narrative to contain, compared
• Activity durations and logic — duration caps, permitted relationship types, lag bans and constraint rules

If you are reviewing a schedule

The schedule review checklist — sorted by what decides each item: the file alone, the governing specification, or a person. Every item also says what it does not prove, which is the part most checklists leave out.

How to audit a Primavera P6 schedule — the P6-specific companion, organised around what the file records versus what the application computes on the fly. The first is evidence; the second is a view.

P6 schedule options — the settings that change the dates, and the specifications that mandate particular values.

If you are choosing or defending a delay method

• Comparing delay methods — method against method, and the undocumented choices that make two competent analysts differ on one file
• Where the standards disagree — AACE, the SCL Protocol, ASCE 67-17 and GAO-16-89G, four documents and no winner named
• Concurrent delay — an authority map, not an answer
• Acceleration, pacing and disruption
• Extension of time — the agency notice clocks side by side
• Who owns the float — three positions in the specifications

If you are checking a schedule against a metric

• The DCMA 14-point metrics — the thresholds as the source states them, and what the checks do not establish
• The GAO Schedule Assessment Guide — four characteristics and ten best practices, in GAO's own wording

If you need to know how a schedule computes

These are about behaviour at the boundaries rather than definitions. The glossary has the definitions.

• Total float and free float
• Constraints
• Lags and leads
• Calendars

If you are working with the files

• What an XER file is
• Decoding clndr_data — how P6 packs a calendar, and why two readers disagree about the same one
• P6 XML, MSPDI and SDEF — what each carries, and what each conversion loses

Everything else

• Glossary
• Questions and answers
• AI and schedule analysis — what reproduces, and what does not

For the documentation of the tool itself rather than the domain, start at the documentation map. For what the tool cannot do, read the limitations before relying on any result.

Source: web/pages/reference.md. Source commit date: 2026-09-11.