write_file

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

No annotations are provided, so the description carries the full burden. It discloses the key behavioral trait of base64 encoding and handling special characters. However, it does not mention other behaviors like overwriting existing files or required permissions, which are reasonable expectations for a file write tool.

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 no wasted words. The first sentence states the action, the second provides usage guidance. Efficient and front-loaded.

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 simple file write tool with no output schema, the description is complete. It explains what it does, how to use it, and when to prefer it over an alternative. The two parameters are fully described in the schema.

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 coverage is 100% with descriptions for both parameters. The description adds context about why base64 encoding is used, which enhances understanding beyond the schema. However, the schema already clearly describes the parameters, so the description adds moderate additional meaning.

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 explicitly states 'Write a file with base64-encoded content.' It clearly identifies the verb (write), resource (file), and distinguishing feature (base64 encoding). It also distinguishes from the sibling tool 'write/filesystem_write_file' by mentioning special character handling.

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 provides explicit guidance: 'Use this instead of write/filesystem_write_file when content contains special chars that break JSON serialization.' This clearly states when to use this tool and offers a specific alternative.

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