fs_write_binary

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

With no annotations, the description must disclose behavioral traits, but it only offers a cryptic reference to '-1 length uses full remaining buffer' despite no length parameter in the schema. It fails to explain base64 decoding, overwrite behavior, or append semantics.

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?

The text is short, but it sacrifices necessary information for brevity and includes a confusing reference to slicing that is not supported by the schema. Under-specification outweighs any conciseness benefit.

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 binary write tool with three parameters and no annotations, the description is fundamentally incomplete. It does not explain input encoding, file handling, or how the append flag interacts with the write.

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 0% and the description adds no meaningful parameter information. It mentions a length concept absent from the schema, and does not clarify file_path, base64_data, or append.

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 states it writes binary bytes, which is a clear verb+resource, and the binary vs. text nature partially distinguishes it from fs_write_text. However, 'sliced' is vague and could imply offset/length parameters that are not present in the schema, making the purpose less crisp.

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?

There is no guidance on when to use this tool versus alternatives such as fs_write_text or fs_read_binary_chunk. No mention of append semantics, file creation behavior, or preconditions is provided.

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