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

With no annotations, the description carries the full burden. It explains the tool returns explanatory text and gives context on the type of content covered. It doesn't mention side effects (none expected for a help tool) or details about behavior when the topic is omitted, but the schema covers that, so the description adds reasonable transparency.

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 description is concise and front-loaded with the purpose, followed by a tight bulleted list of usage scenarios. Every sentence earns its place, and the structure makes it easy to scan. Minor typo ('What is STRING is') does not detract from clarity.

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?

Given the tool is a simple help/FAQ tool with an output schema and a single optional parameter, the description provides sufficient context: what it does, when to use it, and examples of relevant topics. It is complete for its complexity.

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?

The schema describes the 'topic' parameter as optional and notes the behavior when omitted. The tool description adds semantic value by grouping example topics (how_to_use_string, cytoscape, line_colors) into meaningful categories, helping the agent map user questions to appropriate parameter values.

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 provides explanatory text for STRING features and limitations, which is a specific verb+resource. It distinguishes from sibling tools by positioning itself as a help/FAQ tool rather than a data retrieval tool, and reinforces this with example topics.

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?

Explicitly states 'Use this tool when the user question involves:' and lists three distinct scenarios, including guidance for functionality not available via MCP tools. This clearly differentiates when to use this tool versus alternatives.

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