Filing Bug Reports

Filing Bug Reports

Generate a self-contained bug report as a Markdown file that gives a receiving developer everything needed to reproduce the issue — without prescribing root cause or solution.

When to Use

• User asks to file, write, or document a bug
• User wants to hand off a defect for another developer to investigate
• User wants a reproducible record of unexpected behavior

When NOT to Use

• User wants to debug and fix the issue themselves right now — just help them directly
• User wants a design review or code review — use code-review skill instead

Output Conventions

• File: issues/BUG-<NNN>-<slug>.md (next available number, kebab-case slug from title)
• Create the issues/ directory if it doesn't exist
• One bug per file — never combine multiple bugs

Workflow

1. Reconstruct from conversation context. You were present when the bug occurred — use your conversation history to extract:

   • What the user was doing (the action and intent)
   • What actually happened (error messages, tool output, unexpected behavior)
   • What was expected (infer from the user's goal — e.g., if they asked to read a model and got an error, expected behavior is a successful read)

2. Gather environment details programmatically. Don't ask the user for things you can look up:

   • Agent workspace root, OS, architecture: from your system context

   Skill state vocabulary. The skill spec uses progressive disclosure: metadata (name + description) is always in context; the body loads only when triggered. These terms describe the observable states and are agent-agnostic — they hold for any host that implements the Agent Skills standard, not just Claude Code:

   • Registered — the skill appears in the host agent's available-skills list this session.

   • Described — registered AND has a non-empty description in metadata. (Default state, no glyph.)

   • Name-only (⊘) — registered with only a name; the description field is absent from the agent's registration entry. Record which skills are name-only and stop there. Do not read SKILL.md files on disk to verify whether descriptions exist — the available-skills listing is the only state the bug report records. Reading the source frontmatter is cause-investigation, which is out of scope.

     Note: some host agents drop descriptions from the listing automatically when total skill text exceeds an internal budget — for example, Claude Code allocates a character budget that scales with context window size and strips descriptions from least-recently-invoked skills first when the budget is exceeded. Name-only is therefore often expected host behavior in a session with many skills loaded, not a SATK defect. Record the state, but don't frame the bug report as "SATK skill registration is broken" unless the same skill is name-only in a session where the budget clearly isn't exhausted (few skills present, or the host reports no truncation).

   • Invoked (▶) — the skill's body was read into the agent's context this session.

   • Unregistered SATK skill (✗) — a SKILL.md exists on disk under the toolkit's skills-catalog/ but is absent from the available-skills list. ✗ is scoped to SATK only — we don't track unregistered skills from other sources.

   With those definitions:

   • Skills (stack view): read the available-skills list directly (not prior bug reports or docs) and mark each registered skill per the glossary. For ✗, also consult the SATK skill manifest at the toolkit root and list any SATK skills declared there that aren't in the registered set. Render per the Skills subsection of assets/bug-report-template.md.
   • Skill conflict analysis: only consider SATK model-based-design-core skills whose bodies are already in your context, and only if you noticed a conflict between them while doing the work that's plausibly related to this bug. Don't re-read skill bodies to hunt for conflicts; if nothing surfaced naturally, write N/A — <reason>.
   • Available MCP tools: list the MCP tools you have access to
   • Relevant source files: read the files involved in the failure

   SATK-specific (when Simulink MCP tools are available):

   • SATK version: read the VERSION file at the SATK root. If it doesn't exist and a .git/ folder is present, read the latest commit hash and note "development build ()". If neither exists, ask the user what version of Simulink Agentic Toolkit they are using
   • MATLAB: evaluate_matlab_code → disp(version); ver('simulink'); disp(pwd); disp(computer('arch'))
   • SATK toolbox status: evaluate_matlab_code → which('model_read') (empty = toolbox not installed)
   • Connector: evaluate_matlab_code → try; disp(connector.securePort); catch; disp('not running'); end
   • MCP config: read .vscode/mcp.json for server mode and binary path
   • If this is a layout issue and satk status is ok: evaluate_matlab_code → layout.LayoutStateManager.instance().getAnonymizedLayoutSnapshotsPath() but ask user if they agree to share anonymized layout information first. If you get user permission, do not read the contents of the file at the path returned by getAnonymizedLayoutSnapshotsPath, instead use a tool call to append this very large file directly to the final bug report.

3. Reproduce the bug. Re-run the failing operation to confirm it's reproducible and capture exact output. If it passes on retry, note it as intermittent and try to identify what differs.

4. Shrink to a minimal reproduction. Remove every step, file, and variable that isn't needed to trigger the bug. The goal is the smallest input that still fails.

5. Ask the user ONLY for what you cannot determine:

   • Expected behavior — only if the output looks plausible but the user says it's wrong (you can't know what "right" looks like)
   • Severity / business impact — only if it's ambiguous (an outright crash is obviously high; a formatting nit is obviously low)
   • Context from outside this session — if the user references something you didn't witness

6. Write the report using the template in assets/bug-report-template.md. Fill every required section. Mark optional sections N/A if not applicable.

7. Review before saving. Verify:

   • A developer unfamiliar with the project can follow the steps without asking questions
   • No root cause or fix is prescribed (observations and hypotheses go in the Notes section only)
   • Error messages and logs are exact copies, not paraphrased
   • The title follows the format: [Area] — Action — Unexpected result

Guardrails

• Always: Include exact reproduction steps starting from a clean/known state
• Always: Include verbatim error messages and log output (never paraphrase)
• Always: Specify the environment (versions, OS, platform)
• Never: State the root cause — that's the investigator's job
• Never: Propose a fix in the report body (hypotheses go in Notes only, clearly marked as speculation)
• Never: Include secrets, tokens, passwords, or PII — redact with <REDACTED>

References

• assets/bug-report-template.md — The output template (always use this structure)

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