# control_flow > Every PAG keyword record, with what grounds it and how it is checked. Page: Ontology · Grammar Canonical: https://banes-lab.com/ontology/grammar#pag-keywords-control-flow Listed in [Ontology · Grammar](https://banes-lab.com/api/pages/ontology/grammar.md), after [action](https://banes-lab.com/ontology/grammar/pag-keywords-action.md) and before [declaration](https://banes-lab.com/ontology/grammar/pag-keywords-declaration.md). Every PAG keyword record, with what grounds it and how it is checked. ### IF Details Meaning Conditional execution Example IF condition: action Grounds [representation:logic](https://banes-lab.com/records/reasoning/representation-logic.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### ELSE Details Meaning Alternative branch Example ELSE: alternative Grounds [representation:logic](https://banes-lab.com/records/reasoning/representation-logic.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### FOR Details Meaning Iteration start Example FOR EACH item IN list: Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### EACH Details Meaning Iterator marker Example FOR EACH x IN items: Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### WHILE Details Meaning Conditional loop Example WHILE condition: action Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### TRY Details Meaning Exception handling start Example TRY: risky_op Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### CATCH Details Meaning Exception handler Example CATCH: handle_error Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### EXCEPT Details Meaning Exception alternative Example EXCEPT: recovery Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### FINALLY Details Meaning Cleanup block Example FINALLY: cleanup Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### MATCH Details Meaning Pattern matching Example MATCH value: Grounds [representation:logic](https://banes-lab.com/records/reasoning/representation-logic.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### CASE Details Meaning Match branch Example CASE pattern: action Grounds [representation:logic](https://banes-lab.com/records/reasoning/representation-logic.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### DEFAULT Details Meaning Fallback case · a declared default, never a masked failure Example DEFAULT: fallback Grounds [representation:logic](https://banes-lab.com/records/reasoning/representation-logic.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### WHEN Details Meaning Event trigger Example WHEN event: action Grounds [representation:logic](https://banes-lab.com/records/reasoning/representation-logic.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### UNLESS Details Meaning Negated conditional Example UNLESS condition: action Grounds [representation:logic](https://banes-lab.com/records/reasoning/representation-logic.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### UNTIL Details Meaning Loop terminator Example UNTIL done Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### GUARD Details Meaning Early exit check Example GUARD cond ELSE: exit Grounds [representation:logic](https://banes-lab.com/records/reasoning/representation-logic.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### BREAK Details Meaning Exit loop Example BREAK Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### CONTINUE Details Meaning Skip iteration Example CONTINUE Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### GOTO Details Meaning Jump to label Example GOTO label Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### START Details Meaning Flow start marker Example START process Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### END Details Meaning Flow end marker Example END Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### STOP Details Meaning Termination Example STOP Grounds [node:ter-stop](https://banes-lab.com/records/reasoning/node-ter-stop.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### LOOP Details Meaning Loop marker Example LOOP BACKTO step Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### STEP Details Meaning Step marker Example STEP 1: action Grounds [representation:computation](https://banes-lab.com/records/reasoning/representation-computation.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### RULE Details Meaning Rule definition Example RULE name: body Grounds [representation:logic](https://banes-lab.com/records/reasoning/representation-logic.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### IN Details Meaning Containment test Example item IN collection Grounds [representation:logic](https://banes-lab.com/records/reasoning/representation-logic.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ### MATCHES Details Meaning Pattern test Example value MATCHES pattern Grounds [representation:logic](https://banes-lab.com/records/reasoning/representation-logic.md) How it is checked Checked by a structured-document validator that parses each document against the grammar and reports every defect by its shape Population Every agent and template document the validator walks, and every occurrence of the keyword in them Freshness A verdict stands until the grammar data or a document that uses the keyword changes Refusal The validation stage fails the gate on any defect code, so a document with a malformed keyword does not ship Observation None, because a keyword is static text in a document, and nothing observes it while a run executes Evidence Watched to fire and to accept: a suite plants a retired head in a real template and validates every agent and template on disk clean Authoritative side The grammar data, which every keyword in a document conforms to Depends on Not answered Shape it refuses Not answered ## Links to - [Logic](https://banes-lab.com/records/reasoning/representation-logic.md) - [Computation](https://banes-lab.com/records/reasoning/representation-computation.md) - [Stop Condition](https://banes-lab.com/records/reasoning/node-ter-stop.md)