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Equation 4 · Part 8 · The Token Tax of Giving a Model More Tools

subscript

T(n)=τ0+∑i=1nsiT(n) = \tau_0 + \sum_{i=1}^{n} s_i
subscript

What this part means

The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.

Its job in the formula

A subscript distinguishes a version, component, step, or member of a quantity. It does not automatically mean multiplication.

The passage around this formula

Call this fixed, tool-independent charge τ0\tau_0 . On top of it sits the actual content of the catalogue: for n tools attached to a request, each with a schema costing sis_i tokens for its name, description, and JSON Schema of parameters, the tool-visibility component of a single request’s input is T(n)=τ0+∑i=1nsiT(n) = \tau_0 + \sum_{i=1}^{n} s_i. which, if schemas run at roughly a uniform average size sˉ\bar{s} , simplifies to T(n) ≈\approx τ0\tau_0 + nsˉ\bar{s} . Nothing about this term depends on whether the model calls any tool at all; it is the price of the menu, not the price of the order. And critically, because a stateless inference API resends its full input on every request, T(n) is not paid once at the start of a…

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Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

Open the illustrated subscripts: which member of a family? guide →

Sources cited in the article section

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