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Glama

count

Returns the total number of values in a numeric dataset. Provide an array of numbers to measure dataset size.

Instructions

Count the number of values in a dataset.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
numbersYes

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault
resultYes

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.1.0

TDQS

C2.8/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations exist, so the description carries the full behavioral burden, yet it says nothing about edge cases such as empty arrays, whether it counts elements or distinct values, or what the return type is. For a tool with zero structured behavioral coverage, one short sentence is insufficient.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

A single short sentence that is front-loaded with the verb. It wastes no words, though the brevity borders on under-specification rather than true conciseness.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need not be explained, and the tool is simple with one parameter. Still, the description omits edge-case behavior (empty input, distinct vs total count) that matters for a counting tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0% and the description only vaguely refers to 'values in a dataset'. It does not clarify that the lone required parameter is an array of numbers or what form the input takes, so the description fails to compensate for the undocumented schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb (count) and resource (values in a dataset), which is clearer than a bare name. However, it does not differentiate from nearby siblings like sum, mean, or mode, which also operate on a collection of values; the agent must infer the distinction from the name alone.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

There is no indication of when to use count versus the many aggregation siblings (sum, mean, median, variance). No context, prerequisites, or exclusions are provided.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.