Use Sep for high-performance separated-value parsing and writing in .NET, including delimiter inference, explicit parser/writer options, and low-allocation row/column workflows. USE FOR: delimited data needs are performance-sensitive and allocation-aware; project needs explicit control over separator inference, escaping, trimming, and header behavior;. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted f
SkillScore100Maintained
Automatic
◆Coding pack
Last verified 8/19/2026
What it changes
Passed 21 of 21 test cases with the skill, and 9 of 21 without it.
Without skill41%
With skill100%
Checks it passed that the model alone missed
Sets WriteHeader to false in SepWriterOptions.
Calls ToText on the writer specification builder.
Sets Unescape to true in the reader options lambda.
and 13 more in the full report
13 fixed9 passed either way0 still failing0 broke
Pass-rate lift
+59 pp
Tokens
+20%
Agent turns
0%
Response time
-40%
Model gemini-3.6-flashMeasured 8/19/2026v122 of 22 cases passed with skill · 21 comparable
Tokens, turns and time describe resource use, not a dollar price.
See it in action
One of 12 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 12
Prompt
We want to generate a CSV file without writing any header row at the top. Which option in `SepWriterOptions` controls whether headers are written?
What was checked, without and with the skill
Checked
Without skill
With skill
Sets WriteHeader to false in SepWriterOptions.
Missed
Passed
case-19 · gemini-3.6-flash · 8/19/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md137 lines2 files
Sep for .NET separated values
Trigger On
delimited data needs are performance-sensitive and allocation-aware
project needs explicit control over separator inference, escaping, trimming, and header behavior
reading/writing large or long-lived file pipelines in ML, ETL, or analytics workloads
flowchart LR
A[Input source: file/text/stream] --> B[Sep.Reader or Sep.New(...).Reader]
B --> C[SepReaderOptions]
C --> D[Rows -> Cols -> Span/Parse]
D --> E[Transform and validate]
E --> F[SepWriter via SepWriterOptions]
F --> G[To file/text output]
Decide schema shape
header present or no header
separator known (;, ,, tab, custom) or infer from first row
row/column quoting rules
Build reader with Sep.Reader(...) and explicit options only where needed:
Sep.Reader() for inferred separator from header-like first row
Sep.New(',').Reader(...) for explicit separator mode
Use SonarJS-derived rules in .NET repositories that ship JavaScript or TypeScript frontends and need deeper bug-risk, code-smell, or cognitive-complexity checks than a minimal ESLint baseline. USE FOR: SonarQube, SonarCloud, or eslint-plugin-sonarjs setups; frontend code smells; cognitive complexity and deeper bug-risk rules. DO NOT USE FOR: lightweight base lint setups with no extra smell or complexity rules; teams that reject Sonar tooling. INVOKES: inspect the repository context, edit targete