Perplexity Web MCP

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pplx_usage

Check current Perplexity usage limits and remaining quotas before making queries. Use the results to decide whether to conserve premium search and research allowances.

Instructions

Check current Perplexity usage limits and remaining quotas.

CALL THIS AT THE START OF EVERY SESSION before making any queries. Shows remaining Pro Search (weekly), Deep Research (monthly), and other quotas. Use the results to decide whether to conserve Pro quota (e.g. quick intent before premium models).

Args: refresh: Force refresh from Perplexity (ignores cache). Default False.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "pplx_usage"
  }
}

Input Schema

Name	Required	Description	Default
`refresh`	No

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.14.0Jul 4, 2026

TDQS

A4.7/5.0

Behavior4/5

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

With no annotations, description covers behavior well: shows quotas (Pro Search weekly, Deep Research monthly), and explains refresh parameter. Could mention if calling this counts toward usage, but overall strong.

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

Conciseness5/5

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

Three sentences plus args section, front-loaded with purpose and critical usage instruction. Every sentence adds value, no waste.

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

Completeness5/5

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

Output schema likely defines return values, so description need not repeat. Parameter count is 1, well explained. Siblings are many but tool is clearly distinct.

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

Parameters4/5

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

Schema coverage is 0%, but description defines the 'refresh' parameter: 'Force refresh from Perplexity (ignores cache). Default False.' Adds clear meaning beyond schema.

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

Purpose5/5

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

The description clearly states it checks usage limits and remaining quotas, specifying the resource and action. It distinguishes itself from siblings like pplx_ask by focusing on usage information.

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

Usage Guidelines5/5

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

Explicitly says 'CALL THIS AT THE START OF EVERY SESSION' and explains how to use results to decide about conserving Pro quota. Provides clear when-to-use and implied when-not-to-use guidance.

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