bcquality/microsoft/skills/al-performance-review.md

kind	id	version	title	description	inputs	outputs	bc-version	technologies	countries	application-area
action-skill	al-performance-review	1	AL performance review	Reviews AL source changes against performance guidance from BCQuality.	pr-diff file-path	findings-report	26..28	al	w1	all

AL performance review

Reviews AL source changes against the performance knowledge domain in BCQuality and emits a findings report. This is a leaf action skill: it invokes no sub-skills. It is one of the skills composed by al-code-review.

An orchestrator invokes this skill with either a pr-diff (the standard PR-review entry point) or a file-path (single-file review). The skill produces a single JSON document conforming to the DO output contract.

Source

Collect all knowledge files under */knowledge/performance/**/*.md, across every enabled layer (/microsoft/, /community/, /custom/). Relevance trims the result to the subset that applies.

Relevance

Apply the frontmatter matching rules defined in READ (Frontmatter matching semantics) against the task context:

• bc-version — the target BC version from the PR branch's app.json or the orchestrator-supplied version. If unavailable, the dimension is unknown.
• technologies — [al].
• countries — the countries declared in the consuming app's app.json. Default to the orchestrator's configured context; if absent, unknown.
• application-area — the union of application areas declared by the changed objects. Pass the actual set; do not substitute [all]. If the area cannot be determined from the changes, the dimension is unknown.

Discard files that are not applicable. Retain conditionally applicable files (any dimension unknown) only when the orchestrator's configuration permits them; findings derived from those files MUST have confidence no higher than medium, AND the finding's message MUST name the dimension or dimensions that were unknown.

Worklist

Narrow the relevant files to the subset that applies to the changes under review. For each relevant file, compute overlap against:

• The changed AL object names and types — especially tables, pages with SourceTable bindings, reports, queries, and codeunits performing record iteration.
• The changed procedures and triggers, weighted toward those that perform loops, Find/FindSet/FindFirst calls, CalcFields, CalcSums, FlowField access, or cross-table navigation.
• Tokens extracted from the diff that relate to data access (SetRange, SetFilter, SetLoadFields, SetCurrentKey, FindSet, Repeat…Until, CalcFields, CalcSums).

A file enters the candidate worklist when its keywords intersect the extracted tokens or its topic (derived from filename and Description) matches a changed object type.

Once the candidate worklist is known, resolve layer-precedence conflicts per READ. Drop lower-precedence files whose normative guidance (## Best Practice or ## Anti Pattern) directly contradicts a higher-precedence candidate, and record each dropped file in suppressed with reason: "layer-precedence". Files that would have been candidates but are hidden because their layer is disabled in consumer configuration are recorded with reason: "configuration". Files that never became candidates are NOT recorded in suppressed.

When the post-conflict worklist is empty because no applicable performance knowledge exists, or because configuration suppressed every candidate, emit outcome: "no-knowledge". When the worklist is empty because no applicable performance knowledge matched the changes, emit outcome: "completed" with an empty findings array.

Action

For each worklist entry, evaluate the diff against the file's ## Best Practice and ## Anti Pattern sections. Emit findings as follows:

• When the diff contains a clear match for an Anti Pattern, emit a finding with severity major or blocker, a message summarizing the anti-pattern, location pointing to the offending line or range, and a references entry pointing to the knowledge file. Use blocker only when the knowledge file states the anti-pattern violates a platform-level guarantee (for example, documented query timeouts or transaction size limits). When the file does not make such a claim, the ceiling is major.
• When the diff contains code that contradicts a Best Practice without being a full anti-pattern, emit minor with the same reference shape.
• When the skill cannot detect a violation but the file is clearly applicable to the change, emit info citing the file. Repository-wide observations MAY omit location.

Set confidence to:

• high when the detection is based on an unambiguous pattern match (identifier, syntax, object type).
• medium when detection relies on heuristics or when any frontmatter dimension was unknown.
• low when the finding is an advisory derived only from applicability.

Outcome selection:

• completed — the skill evaluated every worklist item; default when the skill finishes normally, including when the resulting findings array is empty.
• no-knowledge — no applicable performance knowledge survived Source, Relevance, configuration filtering, and conflict resolution. findings is empty.
• not-applicable — the task context lacks an AL dimension (no AL changes in the diff, or technologies filter rejected the task).
• partial — a time or token budget was hit before the worklist was exhausted. summary.coverage reflects the evaluated subset; outcome-reason explains the cause.
• failed — an unrecoverable error occurred. outcome-reason is required.

Output

Output conforms to the DO output contract. A populated example:

{
  "skill": { "id": "al-performance-review", "version": 1 },
  "outcome": "completed",
  "summary": {
    "counts": { "blocker": 0, "major": 1, "minor": 0, "info": 1 },
    "coverage": { "worklist-size": 2, "items-evaluated": 2 }
  },
  "findings": [
    {
      "id": "microsoft/knowledge/performance/filter-before-find.md",
      "severity": "major",
      "message": "FindSet is called on a record variable without any prior SetRange/SetFilter. This forces a full-table scan.",
      "location": {
        "file": "src/Sales/PostingRoutines.Codeunit.al",
        "line": 140,
        "range": { "start-line": 140, "end-line": 144 }
      },
      "references": [
        { "path": "microsoft/knowledge/performance/filter-before-find.md" }
      ],
      "confidence": "high"
    },
    {
      "id": "community/knowledge/performance/use-setloadfields.md",
      "severity": "info",
      "message": "Posting routine iterates ledger entries; consider whether SetLoadFields applies per the linked guidance.",
      "references": [
        { "path": "community/knowledge/performance/use-setloadfields.md" }
      ],
      "confidence": "low"
    }
  ],
  "suppressed": []
}

The empty-corpus case — BCQuality's state until performance knowledge files land — produces:

{
  "skill": { "id": "al-performance-review", "version": 1 },
  "outcome": "no-knowledge",
  "summary": {
    "counts": { "blocker": 0, "major": 0, "minor": 0, "info": 0 },
    "coverage": { "worklist-size": 0, "items-evaluated": 0 }
  },
  "findings": [],
  "suppressed": []
}