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xcode_modify_plist

Modify values in plist files to configure Xcode project settings, enabling automated updates to iOS/macOS app properties.

Instructions

Modify a value in a plist file

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": {
      "plist_path": "<plist_path>",
      "key": "<key>",
      "value": "<value>"
    },
    "name": "xcode_modify_plist"
  }
}

Input Schema

Name	Required	Description
`plist_path`	Yes	Path to the plist file
`key`	Yes	Plist key to modify
`value`	Yes	New value for the key

Schema Changelog

Changes observed during successful MCP inspections.

First observedAug 15, 2025

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 the full burden of behavioral disclosure. While 'modify' implies a mutation operation, it doesn't specify whether this requires specific permissions, if changes are reversible, what happens to existing values not mentioned, or potential side effects. This is inadequate for a mutation tool with zero annotation coverage.

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 with zero wasted words. It's appropriately sized and front-loaded, making it easy for an agent to quickly understand the core purpose without unnecessary elaboration.

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?

For a mutation tool with no annotations and no output schema, the description is insufficiently complete. It doesn't explain what happens on success/failure, return values, error conditions, or behavioral nuances. Given the complexity of file modification operations, more context is needed for safe and effective use.

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 description coverage is 100%, with all three parameters clearly documented in the input schema. The description adds no additional parameter semantics beyond what's already in the schema, so it meets the baseline score of 3 for adequate but non-value-adding parameter documentation.

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 ('modify a value') and target resource ('in a plist file'), providing a specific verb+resource combination. However, it doesn't distinguish itself from sibling tools like 'xcode_add_plist_entry' or explain how modification differs from addition, 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 'xcode_add_plist_entry' or 'xcode_read_file'. There's no mention of prerequisites, appropriate contexts, or exclusions, leaving the agent with insufficient usage context.

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