feat(agents): document plain-text path convention for .copilot-tracking artifacts

[vdstrizhkova]

Description

Establishes a formal convention for file references written by subagents into .copilot-tracking/ artifacts. The key principle: when agents cite workspace files in artifact content, use plain-text workspace-relative paths — no markdown links, no #file: directives, no backticks. This prevents VS Code from resolving the paths and flooding the Problems tab with missing-target errors.

The change introduces two complementary reference surfaces:

• Surface A (artifact content): plain-text workspace-relative paths; external URLs may still use markdown links
• Surface B (chat responses): markdown links per existing guidance, now with a boundary note clarifying the distinction

Changes

Subagent File Reference Formatting (8 files)

Added a new standardized ## File Reference Formatting section to:

• .github/agents/hve-core/subagents/implementation-validator.agent.md
• .github/agents/hve-core/subagents/phase-implementor.agent.md
• .github/agents/hve-core/subagents/plan-validator.agent.md
• .github/agents/hve-core/subagents/prompt-evaluator.agent.md
• .github/agents/hve-core/subagents/prompt-tester.agent.md
• .github/agents/hve-core/subagents/prompt-updater.agent.md
• .github/agents/hve-core/subagents/rpi-validator.agent.md
• .github/agents/hve-core/subagents/researcher-subagent.agent.md

Each section restates the plain-text path rule, provides two plain-text examples specific to the subagent's output artifact type, and notes that external URLs may still use markdown syntax.

Removed backticks from inline code examples in response-format pointer lines (e.g., "Re-read " instead of "Re-read <path>") to align with the plain-text convention when those pointers are emitted into artifact files.

Authoring Standard Update (1 file)

Updated .github/instructions/hve-core/prompt-builder.instructions.md to document the two-surface pattern explicitly:

• Added a ## File Reference Formatting template row inside the Subagent Structural Template code block
• Introduced a new ### Surface A: Artifact Content References subsection with the plain-text rule and examples
• Added a boundary sentence to the User-Facing Responses section clarifying that markdown-link guidance applies to chat responses, while artifact content uses plain-text paths

Extended the Subagent Structural Template prose to explain when subagents should include the new File Reference Formatting section (paralleling the existing Required Protocol include/omit guidance).

Related Issue(s)

Closes #2018

Type of Change

• Copilot instructions (.github/instructions/*.instructions.md)
• Copilot agent (.github/agents/*.agent.md)

Testing

Automated validation commands run during the implementation phase:

• npm run lint:md — Passed (236 files scanned, 0 errors)
• npm run lint:frontmatter — Passed (0 errors, 0 warnings)
• npm run lint:ai-artifacts — Passed (70 files scanned, 0 issues)

No manual testing performed. All changes are documentation-only; no runtime or behavioral changes.

Checklist

Required Checks

• Documentation is updated (if applicable) — Authoring standard updated
• Files follow existing naming conventions — All agent and instruction files follow repo conventions
• Changes are backwards compatible (if applicable) — Adds new optional sections; does not modify existing sections
• Tests added for new functionality (if applicable) — Documentation-only; no tests required

AI Artifact Contributions

• Used /prompt-analyze to review contribution — Subagents and instructions reviewed via task planning workflow
• Addressed all feedback from prompt-builder review — Plan Validator findings resolved during planning phase
• Verified contribution follows common standards and type-specific requirements — Frontmatter, markdown, writing style validated

Required Automated Checks

• Markdown linting: npm run lint:md
• Spell checking: npm run spell-check
• Frontmatter validation: npm run lint:frontmatter
• Skill structure validation: npm run validate:skills
• Link validation: npm run lint:md-links
• PowerShell analysis: npm run lint:ps
• Plugin freshness: npm run plugin:generate
• Docusaurus tests: npm run docs:test

Security Considerations

• This PR does not contain any sensitive or NDA information
• Any new dependencies have been reviewed for security issues — No new dependencies added
• Security-related scripts follow the principle of least privilege — No security scripts modified

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 81.36%. Comparing base (3af3352) to head (f376fea).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2147      +/-   ##
==========================================
+ Coverage   81.28%   81.36%   +0.07%     
==========================================
  Files         128      118      -10     
  Lines       18925    18849      -76     
  Branches       12        0      -12     
==========================================
- Hits        15384    15336      -48     
+ Misses       3538     3513      -25     
+ Partials        3        0       -3     

Flag	Coverage Δ
docusaurus	?
pester	86.07% <ø> (-0.02%)	⬇️

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[katriendg]

Verdict: Approve with comments — clean, well-scoped documentation change. All 8 subagents now carry the File Reference Formatting section and the backtick/link cleanup is consistent. A few items to resolve before merge, plus one completeness check against the linked issue.

1. Issue alignment — confirm AC2 & AC3 before auto-close. This PR Closes #2018, whose acceptance criteria include "read-only subagents use the compact pointer response format consistently" (AC2) and "write subagents use the structured template response format consistently" (AC3). The PR delivers the file-reference-formatting and plain-text-path criteria (AC1, AC4) and de-backticks the pointer lines, but I don't see active standardization of the response formats into those two categories. If they were already consistent pre-PR, great — could you note that so closing the issue is accurate? Otherwise consider deferring AC2/AC3 to a follow-up.

2. Markdown lint does not actually cover these files. Heads-up that the "npm run lint:md passed" evidence doesn't validate the changed files: .markdownlint-cli2.jsonc ignores .github/instructions/**, .github/agents/**, .github/prompts/**, and .github/skills/**. I ran markdownlint directly against the PR version and it reports MD004/ul-style violations (see inline). Worth fixing manually since CI won't catch them.

Remaining nits are inline. Nice cleanup overall — the chat-vs-artifact boundary note is a good addition.

[WilliamBerryiii]

Verified — thanks for the thorough review. Confirming for the record:

• MD004 / Surface A-B / phase-implementor rationale (inline threads): all addressed in the current head. markdownlint run directly against all changed .md files reports 0 errors, and there are no remaining dash bullets. Resolving those threads.
• AC2 (read-only -> compact pointer): the validators and researcher-subagent were already consistent; this PR also actively converted prompt-tester and prompt-evaluator from their old free-form requirement lists to the compact pointer format.
• AC3 (write -> structured template): phase-implementor was the existing model and prompt-updater was converted to the full structured template to match.

So closing #2018 on merge is accurate. I verified the above, will resolve the threads and approve. Will just need a quick update with main (branch is currently behind) before merging.

[WilliamBerryiii]

@vdstrizhkova - thanks for the help here ... mering it down!