msd-core/.out-of-scope/agent-template-rendering.md

Render agent definitions from templates at install/config-change time

Source: #2758 Decision: wontfix — closed on the technical merits Date: 2026-05-02

Proposal summary

Move config-gated prose out of agents/*.md into agents/templates/*.md.tmpl, rendered at install time and after .planning/config.json writes via a new gsd-sdk agents render subcommand. Conditional branches resolve at render time (deterministic code) instead of at inference time (LLM interpretation).

Three named benefits:

1. Token reduction proportional to disabled features.
2. Deterministic feature gating (impossible-by-construction vs. test-for).
3. Single source of truth for contributor-facing gating.

Cites PR #2279 (Codex/OpenCode model embedding at install time) as direct precedent for compile-time embedding.

Why GSD does not own this

1. The determinism claim is theoretical, not observed

The proposal's strongest argument is that config-gated branches in agent prose are a determinism failure surface. The actual patterns in the codebase today are already heavily mitigated:

• The use_worktrees branch in gsd-executor is resolved deterministically via gsd-sdk query config-get in bash — it is not LLM-interpreted.
• "Skip if workflow.X is false" prose patterns are short, stable, and follow a uniform "missing key = enabled" convention. There is no documented history of LLMs running disabled checks or skipping enabled ones because of this prose.

A theoretical failure surface should not be traded for a real, high-risk patch-migration surface (gsd-local-patches/ rebase logic, by the reporter's own admission "the highest-risk piece of the change"). The reporter was asked for documented evidence; none was provided.

2. Token waste is small and bounded

The codebase has roughly 5 workflow.* toggle references in agent files and ~20 "Skip if" conditional-prose patterns total — most 1–2 sentences. The "real spend across multi-phase milestones" claim was not measured against gsd-context-monitor output despite being asked. Without a measured baseline, the token-savings argument is asserted rather than demonstrated, and the savings ceiling on ~20 short conditionals is small enough that it does not justify a new template-and-rendering subsystem with a CI-enforced template/generated split.

3. The deterministic-gating need is already served

PR #2279 established orchestrator-time config embedding for the cases that genuinely need deterministic resolution (model selection, reasoning effort, worktree mode). That mechanism is the right layer for orchestration-time decisions and can be extended toggle-by-toggle along the existing path without introducing a parallel templating subsystem. The proposal's own "Alternative #1" (continue the orchestrator-embedding pattern) was rejected on the grounds that agent-internal conditionals belong in the agent layer, but the asks behind the proposal — determinism, lower token cost — are equally satisfied by extending PR #2279 incrementally without a second mechanism.

Adding a templating layer alongside orchestrator-embedding means two mechanisms own the same problem. The proposal does not specify a partition rule, and the reporter did not respond when asked for one.

4. Patch-migration risk is disproportionate to benefit

The /gsd-reapply-patches three-way-merge migration for gsd-local-patches/ is, in the proposal's own words, the highest-risk piece of the change. It exists solely to absorb a contributor-workflow shift — the user-facing surface is unchanged. Risk that flows entirely from internal restructuring, where the benefit is unmeasured token savings and a theoretical determinism gain, is the wrong trade.

The reduced-scope variant (Alternative #5: fresh installs only, defer the migration) avoids that specific risk but still ships a parallel mechanism for benefits that remain unmeasured and that PR #2279's path can absorb.

Re-open criteria

This may be revisited if a contributor:

• Provides measured token deltas via gsd-context-monitor against a representative all-toggles-off config, and the delta is materially larger than what extending PR #2279's orchestrator-embedding path one toggle at a time would produce.
• Documents a real LLM misinterpretation of an existing toggle conditional (executor ignored workflow.use_worktrees: false, verifier ran when workflow.verifier: false, etc.) — not a projected failure mode.
• Proposes a clear partition rule between orchestrator-time embedding (PR #2279) and any new install-time templating layer, so the two mechanisms do not overlap.

Related

• PR #2279 — Codex/OpenCode model embedding at install time (the established precedent for deterministic compile-time embedding into agent files)
• v1.37.0 release notes — shared-boilerplate extraction (reference files for mandatory-initial-read, project-skills-discovery)
• get-shit-done/workflows/ — workflow-level config embedding before subagent spawn (the path of least friction for incremental deterministic gating)