Jiji MCP

jiji_compare_listings

Read-onlyIdempotent

Compare up to eight shortlisted marketplace listings by advertised price, seller signals, and missing information to assess options before contacting sellers.

Instructions

Compare up to eight shortlisted listings, advertised prices, seller signals and missing information. Seller claims remain unverified.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "guids": "<guids>"
    },
    "name": "jiji_compare_listings"
  }
}

Input Schema

Name	Required	Description	Default
`guids`	Yes

Output Schema

Name	Required	Description	Default
`data`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.3.3Oct 29, 2026

TDQS

A3.8/5.0

Behavior4/5

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

Annotations already declare readOnly, idempotent, open-world and non-destructive, so the safety profile is covered. The description adds genuinely new context: that seller claims are unverified, which tells the agent to treat seller-signal data as unconfirmed and to expect 'missing information' to be surfaced rather than filled in.

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?

Two tight sentences with the comparison scope front-loaded and the trust caveat as a closing qualifier. No filler, nothing that could be cut without losing information.

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

Completeness4/5

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 annotations cover the safety profile. What is missing is only the provenance of the guids input; otherwise the definition is sufficient for a one-parameter comparison tool.

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

Parameters3/5

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

Only one parameter (guids), and the description restates the maxItems=8 limit, which the schema already enforces, while saying nothing about the GUID format or where an agent should obtain them (e.g., from jiji_saved_listings). With 0% schema description coverage and one param, the schema constraints carry most of the meaning.

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?

Names a specific verb (Compare) and a specific resource (shortlisted listings) with a stated cap of eight, plus the dimensions compared (advertised prices, seller signals, missing information). It implicitly separates itself from single-listing siblings like jiji_listing_details, but never names an alternative explicitly, keeping it just short of a 5.

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

Usage Guidelines3/5

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

The phrase 'shortlisted listings' implies the right context (listings already surfaced/saved rather than a fresh search), but there is no explicit when-to-use statement, no when-not, and no named alternative such as jiji_listing_details for a single listing or jiji_search for discovery. Usage has to be inferred.

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