Independent API referenceField notes updated 29 Aug 2026

Performance guide

Estimate and reduce tool schema token cost

Estimate tool-definition prompt weight and reduce it without deleting the descriptions models need for reliable routing.

Approximate token weightActive-tool pruningDescription valueDuplicate schema detection

Reviewed Source: Gemini function calling guide

Tool definitions consume context. The answer is not indiscriminate minification: names, descriptions, and enum meaning help routing, while duplicated boilerplate and inactive tools often do not.

Read the schema and its provider wrapper as one contract. APITC distinguishes target requirements from portable JSON Schema, applies mechanical repairs only when intent is recoverable, and identifies transformations that can change meaning.

Diagnostic procedure

Repair the schema, then recompile.

  1. 01

    Measure the compiled target

    Provider wrappers and strict repairs can materially change size, so measure output rather than only source.

  2. 02

    Prune by turn

    Expose the smallest relevant tool set for the current workflow.

  3. 03

    Compress repetition

    Shorten duplicated boilerplate before removing discriminating descriptions.

Before
Every request includes 80 tools and repeated authentication prose.
Target-safe shape
Route first, then provide 5–10 relevant tools with concise, distinct descriptions.

Interactive check

Run the schema against a real target.

Paste JSON, choose a target, and inspect the compiled shape and every portability warning before copying the result.

Contract compilerlocal browser runtime
01 Source contract APITC canonical
02OpenAI strict
80compatibility
0 errors · 2 fixes · 0 warnings
fix$.inputSchemaClose this object

OpenAI strict requires additionalProperties: false on every object.

fix$.inputSchemaRequired array is incomplete

Strict mode requires every property in required. APITC will make limit nullable.

97 tokens compiled · input never leaves this tab

No account · no upload · no endpoint calledOpen the full tool schema compiler and operating notes →

FAQ

Before you ship

Does APITC upload my schema?

No. Parsing, diagnostics, and compilation run in your browser tab.

Is the compiled result guaranteed to preserve meaning?

Safe repairs are deterministic. When the target provider cannot express a source constraint, APITC labels the transform as lossy instead of hiding it.

Protocol behavior checked against the Gemini function calling guide. Recheck your pinned provider/API version before production deployment.