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Working code for AI systems, clear diagrams, and the parts that only show up in production.

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Explainer12 min read

When the tool catalog becomes the prompt

A 192-run Microsoft.Extensions.AI benchmark compares sending 8 or 64 tools on every request with a RequestTools discovery function. At 64 tools, billed tokens drop by about 2.5x. At 8 tools, the extra round trip costs more than it saves.

AI systemsReliability
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examples/ProgressiveCatalogUsage.cs
ToolCatalog catalog = new ToolCatalogBuilder()
    .AddTool("github", githubSearch)
    .AddTool("jira", jiraSearch)
    .AddTool("database", queryDatabase, tags: ["sql", "postgres"])
    .Build();

AIFunction requestTools = catalog.CreateRequestToolsFunction();

Register the catalog in process. Put RequestTools on the request. Attach matches during the function loop.

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alex-janjic/ContextWindow.Extensions.AI

A progressive tool catalog for Microsoft.Extensions.AI with deterministic selection, compatibility tests, and benchmark suites.

examples/ProgressiveCatalogUsage.csStart here

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