Write text content as a new file inside a JAR archive. Use it to add configs, manifests, or resources to Java-based game mods during patching.
Write text content as a new file in the JAR.
| Name | Required | Description | Default |
|---|---|---|---|
| content | Yes | File content | |
| encoding | No | Encoding (default: utf-8) | |
| jar_path | Yes | Destination path within JAR | |
| session_id | Yes | Session ID |
Changes observed during successful MCP inspections.
v0.1.4Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It does not say what happens if the file already exists (overwrite vs error), whether the session must be open, or whether the change is reversible or persisted to disk on jar_repack.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single front-loaded sentence with no wasted words. It is efficient, though its brevity edges toward under-specification rather than tight conciseness.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a 4-parameter mutation tool with no annotations and no output schema, the description omits the behavioral details an agent needs: overwrite semantics, session lifecycle, and encoding interaction. The name and schema cover the what, but the how and the risks are unaddressed.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so all four parameters (content, encoding, jar_path, session_id) are already documented in the schema. The description adds no syntax, format, or path conventions beyond that, so the baseline 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb (Write) and resource (text content as a new file in the JAR), which lets an agent distinguish it from a read tool like jar_read_file. It does not, however, differentiate itself from the closely named sibling jar_add_file, leaving the choice between them ambiguous.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description gives no when-to-use guidance, no prerequisites, and no mention of alternatives. The existence of jar_add_file and jar_edit_file as siblings makes the absence of routing guidance a real gap.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.