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 CrestApps/CrestApps.AgentSkills --skill crestapps-core-file-sourcesgit clone --depth 1 https://github.com/CrestApps/CrestApps.AgentSkillsWrote 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/crestapps/crestapps.agentskills/crestapps-core-file-sources)<a href="https://agentmods.dev/skills/crestapps/crestapps.agentskills/crestapps-core-file-sources"><img src="https://agentmods.dev/badge/skills/crestapps/crestapps.agentskills/crestapps-core-file-sources/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/crestapps/crestapps.agentskills/crestapps-core-file-sources"><img src="https://agentmods.dev/badge/skills/crestapps/crestapps.agentskills/crestapps-core-file-sources.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 | $0.00178 | $0.02696 |
| Opus 5.5 | $0.00071 | $0.01078 |
| Sonnet 5.5 | $0.00036 | $0.00539 |
| Haiku 4.5 | $0.00018 | $0.00270 |
Grade A, and why
crestapps-core-file-sources 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 yesterday.
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 — 173 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CrestApps.Core File Sources
A File AI data source (AIDataSourceSourceTypes.File) is an inert bucket with no folder, credential or field mapping. A file source (FileSource record) picks a connector, configures it, and points at the File data source it fills. Several file sources can feed one knowledge base, each on its own schedule. Web crawlers (crestapps-core-web-crawlers) are the same shape for websites.
FileSource (FileSystem) -+
FileSource (Ftp) -+-> File AI data source -> knowledge-base index (typed objects)
FileSource (Sftp) -+
Each file becomes separately retrievable objects (document, article, text, figure, chart, table) with a page number and a link to its article and document. Data source concepts are in crestapps-core-data-sources; readers and figure processing are in crestapps-core-document-processing.
Registration
using CrestApps.Core.AI.Documents;
using CrestApps.Core.AI.Documents.Endpoints;
using CrestApps.Core.AI.FileSources;
using CrestApps.Core.AI.Ftp;
using CrestApps.Core.AI.Sftp;
using CrestApps.Core.Data.YesSql;
builder.Services.AddCrestAppsCore(crestApps => crestApps
.AddAISuite(ai => ai
.AddOpenAI()
.AddDocumentProcessing(documentProcessing => documentProcessing // optional: chat uploads, Office readers
.AddYesSqlStores()
.AddPdf()
.AddReferenceDownloads()))
.AddIndexingServices(indexing => indexing
.AddYesSqlStores()
.AddPostgreSQL(
builder.Configuration.GetSection("CrestApps:PostgreSQL"),
postgreSQL => postgreSQL.AddAIDataSources())));
// After AddDocumentProcessing, so the HTML reader registered here wins .html.
builder.Services
.AddCoreFileSources(builder.Configuration)
.AddCoreFileSystemConnector()
.AddCoreFtpIngestionConnector() // CrestApps.Core.AI.Ftp (FluentFTP)
.AddCoreSftpIngestionConnector(); // CrestApps.Core.AI.Sftp (SSH.NET)
builder.Services.AddCoreFileSourceStoresYesSql(); // or AddCoreFileSourceStoresEntityCore()
var app = builder.Build();
app.AddDownloadKnowledgeFigureEndpoint();
What ships with it
1 file 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.
- yesterday First seen · 173 lines · 178 tokens per session scan A 07288b98e4b9
crestapps-core-file-sources is a skill published in the GitHub repository CrestApps/CrestApps.AgentSkills (13 stars, last pushed yesterday), licensed MIT. It adds 178 tokens to every session and 2,696 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 2026-10-22.
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