pet-tools-mcp

Overview Schema Source Related Servers Discussions Admin

pet_reg_get

Read CPU register values and retrieve the program counter annotated with nearest symbol from a loaded label file for debugging Commodore PET software.

Instructions

Read CPU registers. PC is annotated with the nearest symbol when a label file is loaded.

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": "pet_reg_get"
  }
}

Input Schema

Name	Required	Description	Default
`session`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Jul 11, 2026

TDQS

B3.3/5.0

Behavior3/5

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

With no annotations, the description carries full burden. It discloses that PC is annotated with the nearest symbol if a label file is loaded, but does not mention other registers, side effects, or whether the tool is read-only. Adequate but minimal.

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

Conciseness4/5

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

The description is concise with two well-structured sentences. The first states purpose, the second adds a specific detail. No wasted words, though it could benefit from a more structured explanation including parameter and output info.

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?

Given the tool's simplicity (one optional param, no output schema), the description covers core behavior but omits expected return format and any explanation of the session parameter. Complete enough for basic use but not fully informative.

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

Parameters1/5

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

The input schema has one parameter 'session' with no description (0% coverage). The description does not explain 'session' at all, leaving the agent without guidance on its meaning or usage. The tool name and description add no value beyond the 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 'Read CPU registers', which is a specific verb and resource. It distinguishes from siblings like pet_reg_set (write) and pet_mem_read (memory). The added detail about PC annotation further specifies behavior.

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 description implies usage for reading CPU registers, but does not explicitly state when to use or not use this tool, nor does it mention alternatives like pet_reg_set for writing. No guidance on context or prerequisites.

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