Mercado Libre MCP Server

update_price

Update a Mercado Libre listing's price and return the previous and new prices to confirm the change.

Instructions

Actualiza el precio de una publicación en Mercado Libre. Retorna precio anterior y nuevo para confirmación.

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": {
      "item_id": "<item_id>",
      "price": "<price>"
    },
    "name": "update_price"
  }
}

Input Schema

Name	Required	Description	Default
`price`	Yes	Nuevo precio en la moneda de la publicación
`item_id`	Yes	ID de la publicación (ej: MLA1234567890)

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.2.0-alpha.3Nov 8, 2026

TDQS

B3.4/5.0

Behavior3/5

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

With no annotations, the description carries the full behavioral burden, and it does disclose the return payload ('precio anterior y nuevo para confirmación'), which is genuinely useful for a mutation. However, it says nothing about permissions/scopes required, whether the change takes effect immediately, or side effects on active promotions or listing status.

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 compact sentences with zero filler; the action is front-loaded and the return behavior follows. Nothing is repeated from the schema or wasted.

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?

For a simple two-parameter mutation with full schema coverage and no output schema, the description covers the action and the confirmation payload an agent needs. The remaining gap is the lack of routing guidance toward sibling pricing tools, which is minor given the tool's simplicity.

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?

Schema description coverage is 100%, with both parameters documented (price as a positive number in the listing's currency, item_id with an MLA example). The description adds no syntax, formatting, or validation detail beyond what the schema already provides, so the baseline 3 applies.

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 and resource ('Actualiza el precio de una publicación en Mercado Libre'), which clearly distinguishes it from read-oriented siblings like price_history or price_to_win. It never names a sibling explicitly, so differentiation is inferred rather than stated.

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 guidance on when to use this tool versus related ones such as price_history (to inspect) or price_to_win (to decide a target price). The description only implies usage through the verb 'Actualiza', leaving prerequisites and exclusions unstated.

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

Deploy Server