A traditional tracker exposes state. tik exposes justification: what is true, why it is true, and what evidence is missing next. tik explain is where that surfaces, and every other view is a rendering of it.

$ tik explain 3184
To reach :resolved:
  ✓ [:fact [:resolution :ref]]
  ✗ attach an artifact whose path starts with "repro/"
  blocks: :closed
  (see: kb/runbooks/support-request-resolved.md)

Nothing in that block is speculation. The checkmarks are guards that already hold, the crosses are structured reasons produced by guard evaluation, blocks is the downstream closure, and the hint is the runbook the definition declares for that stage.

Reasons are data

The prose lives in this lens only. Underneath, each missing step is a structured reason carrying the path, the schema, the role, the actor whose signature already counted — whatever the guard knows:

tik explain 3184 --edn

That data contract is stable plumbing; the English is not. It renders as CLI text, as web forms built from the schemas in the reasons, and as agent task specifications whose acceptance criteria are the guards.

Reasons are sorted by who can act on them right now: values anyone can supply first, then corrections, artifacts, specific people, attestations, other stages, and finally time, which is nobody’s to act on.

Who can act

--actor filters a block to what one person can do, and counts the rest rather than hiding it:

$ tik explain 3184 --actor alice
To reach :resolved:
  ✗ attach an artifact whose path starts with "repro/"
  … 1 step(s) waiting on others or time

tik next rotates the same derivation into an inbox — for a person, or for a whole role:

tik next --actor alice
tik next --role :triager

The inbox ranks by unlock impact, so the step that frees the most downstream work comes first, and it holds back tickets whose dependency links point at unsettled upstream work.

Waiting versus impossible

Some blocked tickets are waiting for a colleague. Others can never move at all — a role with no members, a negation over a sticky stage already reached, a prerequisite that is itself dead. Those look identical until you say so, and telling somebody to wait for something that will never arrive is the failure that matters most for a tool whose whole claim is answering what is blocking.

$ tik explain 9c21
To reach :approved (unreachable):
  ⊘ fact [:sign-off] must be asserted by a member of role :auditor
      (currently by "seb") — nobody can ever do this

The derivation stays conservative: a step is only called impossible when it is provably undischargeable from the definition and the log. A choice dies only when every one of its branches does. Anything merely waiting keeps its ✗.

Proving it

tik causal answers the auditor’s question — which signed events made each reached stage true, with negations and time saying so honestly:

tik causal 3184

And tik whatif asks the counterfactual without writing anything:

tik whatif 3184 severity=:low +P2D retract:category