Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add DevExpress/agent-skills --skill devexpress-xaf-validationgit clone --depth 1 https://github.com/DevExpress/agent-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/devexpress/agent-skills/devexpress-xaf-validation)<a href="https://agentmods.dev/skills/devexpress/agent-skills/devexpress-xaf-validation"><img src="https://agentmods.dev/badge/skills/devexpress/agent-skills/devexpress-xaf-validation/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/devexpress/agent-skills/devexpress-xaf-validation"><img src="https://agentmods.dev/badge/skills/devexpress/agent-skills/devexpress-xaf-validation.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00164 | $0.02765 |
| Opus 5.5 | $0.00066 | $0.01106 |
| Sonnet 5.5 | $0.00033 | $0.00553 |
| Haiku 4.5 | $0.00016 | $0.00277 |
Grade A, and why
devexpress-xaf-validation scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 192 lines — stays where its author put it; the contents beside it link to each section on GitHub.
DevExpress XAF — Validation
Data integrity enforcement through declarative rule attributes and programmatic validation.
Prerequisites & Installation
NuGet Packages
| Package | Purpose | Project |
|---|---|---|
DevExpress.ExpressApp.Validation |
ValidationModule, rule attributes (RuleRequiredField, RuleCriteria, etc.), IRuleSet, DefaultContexts |
MySolution.Module |
DevExpress.ExpressApp.Validation.Blazor |
Blazor validation UI (error dialogs, inline messages) | MySolution.Blazor.Server |
DevExpress.ExpressApp.Validation.Win |
WinForms validation UI | MySolution.Win |
Module Registration
Blazor — MySolution.Blazor.Server\Startup.cs:
using DevExpress.ExpressApp.Validation;
services.AddXaf(Configuration, builder => {
builder.Modules
.AddValidation(options => {
// Optional: subscribe to validation events
// options.Events.OnCustomNeedToValidateRule = context => { ... };
});
});
WinForms — MySolution.Win\Startup.cs:
builder.Modules
.AddValidation();
Using Statements for Business Classes
using DevExpress.Persistent.Validation; // Rule attributes, DefaultContexts, ResultType
Built-in Validation Rules
All 11 built-in rule attributes. Each requires a unique rule ID (first string parameter) that identifies the rule in results, events, and troubleshooting. The rule ID must be unique within the module.
| Rule Attribute | Purpose | Example |
|---|---|---|
RuleRequiredField |
Property must have a non-null/non-empty value | [RuleRequiredField("NameRequired", DefaultContexts.Save)] |
RuleCriteria |
Object must satisfy criteria expression | [RuleCriteria("EndAfterStart", DefaultContexts.Save, "EndDate > StartDate")] |
RuleRange |
Value within min/max inclusive bounds | [RuleRange("DiscountRange", DefaultContexts.Save, 0, 100)] |
RuleRegularExpression |
Value matches .NET regex | [RuleRegularExpression("EmailFormat", DefaultContexts.Save, @"^[\w.-]+@[\w.-]+\.\w+$")] |
RuleValueComparison |
Value compared against constant | [RuleValueComparison("PositiveAmount", DefaultContexts.Save, ValueComparisonType.GreaterThan, 0)] |
RuleStringComparison |
String compared against constant | [RuleStringComparison("CodePrefix", DefaultContexts.Save, StringComparisonType.StartsWith, "A")] |
RuleUniqueValue |
Value must be unique (DB query) | [RuleUniqueValue("UniqueCode", DefaultContexts.Save)] |
RuleCombinationOfPropertiesIsUnique |
Property combination unique | [RuleCombinationOfPropertiesIsUnique("UniqueDeptTitle", DefaultContexts.Save, "Department;Title")] |
RuleFromBoolProperty |
Boolean property must be true | [RuleFromBoolProperty("AcceptedTerms", DefaultContexts.Save)] |
RuleIsReferenced |
Object must be referenced (Delete) | [RuleIsReferenced("DeptHasEmployees", DefaultContexts.Delete, typeof(Employee), "Department")] |
RuleObjectExists |
Object matching criteria must exist | [RuleObjectExists("ManagerExists", DefaultContexts.Save, "IsManager = true")] |
What ships with it
5 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 10d ago First seen · 192 lines · 164 tokens per session scan A c43b5138db4a
devexpress-xaf-validation is a skill published in the GitHub repository DevExpress/agent-skills (66 stars, last pushed 11d ago), licensed MIT. It adds 164 tokens to every session and 2,765 once invoked, about $0.0007 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-10-20.
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