Skip to main content
Glama
Sign In
OBS MCP

OBS MCP

by Tom-R-Main
OverviewSchemaSourceRelated ServersDiscussionsAdmin
Rust
Hybrid

Send Stream Caption

obs-send-stream-caption

Send CEA-608 caption text to your live stream output. Deliver real-time captions to viewers, ensuring accessibility for all audiences.

Instructions

Sends CEA-608 caption text over the stream output

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": {
      "captionText": "<captionText>"
    },
    "name": "obs-send-stream-caption"
  }
}

Input Schema

NameRequiredDescriptionDefault
captionTextYesCaption text to send

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv1.1.1

TDQS

B3.3/5.0
Behavior2/5

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

The annotations indicate readOnlyHint=false and idempotentHint=false, implying a mutating, non-idempotent operation, but the description adds no extra details about side effects, rate limits, or whether captions are replaced or appended. It does not contradict annotations, but fails to enrich transparency.

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, focused sentence that directly states the action and target. It is concise with no redundancy or irrelevant information, making it easy to parse and understand.

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?

The description is adequate for a simple 'send' action, but it omits context such as error conditions, requirements (e.g., must be streaming), or whether the caption replaces or appends to existing captions. Given the tool's simplicity, the description is minimally complete but could be more informative.

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?

The schema already describes the single parameter 'captionText' as 'Caption text to send', and the tool description repeats this without adding new details (e.g., length limits, encoding, or special formatting). With high schema coverage, the baseline is 3, and the description adds no additional value.

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 the tool's function: sending CEA-608 caption text over the stream output. It uses a specific verb ('sends') and resource ('stream output'), distinguishing it from sibling tools that handle scenes, inputs, or streaming controls.

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 does not provide any guidance on when to use this tool versus alternatives. It lacks context about prerequisites (e.g., active stream, caption format) or conditions under which it should be invoked. Usage is implied but not explicitly stated.

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

Deploy Server

Other Tools