add_block

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

With no annotations, the description fully discloses that the tool is unconditional and creates duplicates: 'Calling it twice creates two separate blocks of the same type.' This goes beyond basic safety to clear behavioral expectation.

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 long but well-structured with key warning upfront and organized type list. Every sentence provides value, though brevity could slightly improve. Still, it earns its length for 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 complexity (mutation tool, many siblings, no output schema), the description covers usage, type mapping, and alternatives. Missing explicit mention of return value, but the comprehensive guidance makes it usable.

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%, so baseline is 3. The description does not add new semantic meaning to parameters beyond what the schema provides. While it maps types to alternative tools, that is usage guidance, not parameter semantics.

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 'add_block creates a new block unconditionally,' uses a specific verb (create) and resource (block), and distinguishes from sibling tools like ensure_block and type-specific tools (e.g., add_colors).

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 warns to prefer ensure_block and specifies 'Only use add_block when you have already confirmed via list_blocks that no block of this type exists.' Also provides alternative tools per block type, giving clear when-to-use and when-not-to-use guidance.

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