save_snapshot

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

With no annotations provided, the description carries the full burden. It discloses that the tool writes a PNG file to disk and returns a path, but it does not mention overwrite behavior, where the file is stored, or whether an active session is required.

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?

Two sentences, with the core operation front-loaded and the usage scenario following immediately. Every part adds useful information, with no wasted words.

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 zero-parameter tool with no output schema, the description covers the main operation, the return value, and the practical use case. Minor gaps around file location and system prerequisites are acceptable at this level of simplicity.

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?

There are no parameters, so there is no schema gap to compensate for; this earns the baseline 4. The description adds only relevant context by referring to 'current handwriting'.

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?

The description clearly states the tool's action: saving the current handwriting as a PNG file on disk and returning its path. This is specific, uses a clear verb, and is easily distinguished from sibling tools like get_handwriting or get_connection_info.

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?

It explicitly states when to use this tool: when images cannot be received through MCP directly, telling the agent to read the file instead. It does not name a specific sibling alternative, but the fallback scenario is clear.

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