fast-filesystem-mcp

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

With no annotations provided, the description carries full burden. It mentions behavioral traits like streaming, retry, backup, and verification, which go beyond basic writing. However, it lacks details on error handling, performance implications, or what 'reliably' entails in practice.

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?

Extremely concise single sentence that front-loads the core purpose and lists key features efficiently. Every word earns its place with zero redundancy.

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 complex write tool with 10 parameters and no annotations/output schema, the description is minimal but covers key behavioral aspects. It hints at advanced features but lacks completeness on error cases, performance trade-offs, or output details.

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 parameters are well-documented in the schema. The description adds no specific parameter semantics beyond implying that parameters enable the mentioned features (e.g., retry_attempts for retry). Baseline 3 is appropriate as the schema does the heavy lifting.

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 purpose: 'Reliably writes large files' with specific features listed (streaming, retry, backup, verification). It distinguishes from 'fast_write_file' by emphasizing large file handling and reliability features, though it doesn't explicitly name that sibling for comparison.

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?

No explicit guidance on when to use this tool versus alternatives like 'fast_write_file' or 'fast_safe_edit'. The description implies it's for large files with reliability needs, but doesn't specify thresholds (e.g., file size) or contrast with simpler write operations.

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