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Add and test declarative behavior-defined agentic engines in gh-aw, extending Go infrastructure only when necessary.
Passed 18 of 23 test cases with the skill, and 7 of 23 without it.
and 11 more in the full report
11 fixed7 passed either way5 still failing0 broke
Tokens, turns and time describe resource use, not a dollar price.
One of 11 test cases the skill fixed. Same model, same prompt, with and without the skill.
After extending the Go structs in engine_definition.go and updating main_workflow_schema.json, what Makefile command must be run if the generated schema documentation changes?
| Checked | Without skill | With skill |
|---|---|---|
| Specifies running `make generate-schema-docs` | Missed | Passed |
The instructions your model reads when the skill loads.
Use this skill when adding a new agentic engine definition or extending the behavior-defined engine infrastructure.
Prefer a shared Markdown engine definition. Installation, execution, MCP
configuration, provider routing, caching, manifests, plugins, network defaults,
harness scripts, and log parsing can already be declared through
engine.behaviors.
Only change Go code when the engine needs a reusable behavior that the declarative model cannot express. Add a dedicated Go engine only when the shared behavior-defined runtime cannot run the engine at all.
| Need | Implementation |
|---|---|
| Existing behaviors are sufficient | Add an imported shared engine definition |
| A reusable declarative behavior is missing | Extend the definition model and behavior-defined runtime |
| The shared runtime is fundamentally unsuitable | Add a dedicated Go engine and register it |
The relevant implementation is in:
pkg/workflow/engine_definition.go for the definition model and catalogpkg/workflow/behavior_defined_engine.go for the shared runtimepkg/workflow/engine_definition_loader.go for embedded built-in definitionspkg/workflow/agentic_engine.go for dedicated Go engine registrationpkg/parser/schemas/main_workflow_schema.json for the workflow schemaRead the closest examples before making changes:
.github/workflows/shared/opencode.md: npm installation, merged
configuration, MCP, provider routing, and log parsing.github/workflows/shared/aider.md: Python installation and a custom harness
without native MCP.github/workflows/shared/crush.md: native MCP configuration adapter and
harnesstest cases passed, vs 7 / 23 without
More skills from the same source and nearby in the registry, with their headline benchmark lift.