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write_json_values

Modify JSON files by writing values to specific paths using dot notation. Automatically creates missing paths to update configurations, multilingual content, or structured data.

Instructions

Write a value to a JSON file at a specified path using dot notation. Creates missing paths automatically.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
filePathYesAbsolute path to the JSON file
pathYesDot notation path to the value (e.g., "common.welcome")
valueYesValue to write (any JSON-serializable type)
Behavior3/5

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. It adds useful context about automatic path creation, which is a key behavioral trait not implied by the name alone. However, it doesn't cover other important aspects like file overwriting behavior, error handling, or permissions required, leaving gaps for a mutation tool.

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 front-loaded with the core purpose in the first sentence and adds a critical behavioral detail in the second. Both sentences earn their place by providing essential information without redundancy, making it highly efficient and well-structured.

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 complexity as a file mutation operation with no annotations and no output schema, the description is adequate but incomplete. It covers the basic action and path creation, but lacks details on return values, error cases, or side effects, which are important for safe usage in a broader context.

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%, so the input schema already documents all parameters thoroughly. The description adds minimal value beyond the schema by implying the 'path' parameter uses dot notation and the 'value' is JSON-serializable, but it doesn't provide additional syntax or format details, meeting the baseline for high schema coverage.

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 specific action ('Write a value'), target resource ('JSON file'), and mechanism ('using dot notation'), distinguishing it from sibling tools like 'read_multiple_json_values' and 'delete_multiple_json_values' by focusing on writing rather than reading or deleting.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides clear context for usage ('Creates missing paths automatically'), which helps understand when to use this tool for path creation. However, it lacks explicit guidance on when to use alternatives like 'merge_duplicate_keys' or when not to use this tool, such as for bulk operations or deletions.

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

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