IMP-076: Explain contract execution, evaluation and returned results

content/docs/declare-outcomes.mdx

@@ -7,8 +7,7 @@ description: Express intent through requirements. Reuse and combine contracts wh
 
 # Contract authoring
 
-State what the agent must accomplish, which requirements it must satisfy, and
-where it can choose its approach. **Contract authoring is expressing intent by
+**Contract authoring is expressing intent by
 composing requirements.** A contract states those requirements and the context
 needed to interpret and apply them.
 
@@ -20,6 +19,33 @@ concrete; it does not by itself establish that the result is accurate.
 
 <span id="instructions-decay-outcomes-endure" />
 
+## Execution and evaluation
+
+An agent performs the work, and an evaluator assesses whether the contract's
+requirements are satisfied. The **executor** performs the work and returns a
+**result** that includes the evidence needed for assessment. The **evaluator**
+returns an **assessment**: its findings about the contract and the evidence.
+Execution and evaluation repeat as needed. Evaluation can also assess the
+current state before further execution.
+
+These are roles. The same agent can perform both unless a composed contract
+requires independence. A decision model can perform evaluation. Authors
+compose contracts for evidence, review and authorization just as they compose
+contracts for the rest of the work.
+
+A result can be a long document containing or referencing artifacts and
+records. Keep its references accessible to the evaluator. Evidence belongs in
+the result, not in a separate return value. Fulfillment means satisfaction of
+the contract's applicable requirements; returning a result does not establish
+fulfillment by itself.
+
+Use **out** for the normal result channel and **error** for execution failure.
+An evaluator can return a normal assessment that finds unmet requirements or
+insufficient evidence in its subject. Preserve partial work and effects when
+execution fails. These concepts map to the selected runtime's existing
+interfaces: function returns, responsibility state and receipts, and declared
+errors. They do not add syntax or prescribe operating-system streams.
+
 ## Requirements and approaches
 
 A requirement states a condition the work must satisfy. An approach describes

content/docs/index.mdx

@@ -1,15 +1,16 @@
 ---
 title: OpenProse
-description: State what an agent must accomplish, which requirements it must satisfy, and where it can choose its approach. Reuse and combine Markdown contracts.
+description: Express intent by composing requirements. Execute contracts and evaluate results.
 ---
 
 # OpenProse
 
-**With OpenProse, you state what an agent must accomplish, which requirements it
-must satisfy, and where it can choose its approach.** Contract authoring is
+Contract authoring is
 expressing intent by composing requirements. Reusable contracts provide the
 building blocks; composition determines how their requirements apply together.
 
+An agent performs the work, and an evaluator assesses whether the contract's requirements are satisfied. The executor returns a result that includes evidence for the assessment. Execution and evaluation repeat as needed.
+
 These docs cover the public `open-prose` skill's **Contract Markdown and
 ProseScript** format. A `responsibility` expresses requirements for information
 or conditions maintained over time. A `function` provides a one-time call.