Replit MCP Server

set_secret

Set environment variables or secrets for Replit workspaces to configure application settings and secure sensitive data.

Instructions

Set an environment variable/secret for a repl

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": {
      "key": "<key>",
      "value": "<value>"
    },
    "name": "set_secret"
  }
}

Input Schema

Name	Required	Description
`key`	Yes	The name of the environment variable
`value`	Yes	The value of the environment variable
`replId`	No	Optional repl ID (uses active repl if not specified)

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Jan 10, 2026

TDQS

C2.9/5.0

Behavior2/5

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

With no annotations provided, the description carries full burden for behavioral disclosure. It implies a mutation ('Set'), but doesn't specify if this creates or updates secrets, what permissions are required, whether changes are reversible, or any rate limits. This leaves significant gaps for a tool that modifies data.

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?

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It is appropriately sized and front-loaded, with no wasted content.

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

Completeness2/5

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

Given this is a mutation tool with no annotations and no output schema, the description is insufficient. It lacks details on behavioral aspects like permissions, side effects, or return values, which are critical for safe and effective use in context with sibling tools.

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%, so the input schema already documents all parameters (key, value, replId) with descriptions. The description adds no additional semantic context beyond what's in the schema, such as format examples or constraints, meeting the baseline for high coverage.

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?

The description clearly states the action ('Set') and resource ('environment variable/secret for a repl'), making the purpose understandable. However, it doesn't explicitly differentiate from sibling tools like 'delete_secret' or 'get_secrets' beyond the verb, which prevents a perfect score.

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?

The description provides no guidance on when to use this tool versus alternatives like 'delete_secret' or 'get_secrets', nor does it mention prerequisites such as needing an active repl or permissions. It only states what it does, not when or why to use it.

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