add

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

The description states it returns the sum, which is clear. With no annotations, the description covers basic behavior well. However, it does not address edge cases like overflow or NaN handling, but for a simple arithmetic tool this is acceptable.

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 extremely concise with only two lines plus an optional docstring. It is front-loaded with the core purpose and includes the necessary args and returns sections with no wasted words.

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 low complexity (2 required numeric parameters, no output schema, no annotations), the description fully explains what the tool does and what it returns. It is complete for its scope.

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 input schema covers both parameters with types, but schema description coverage is 0%. The description adds that it returns the sum, which is not in the schema. However, the schema already defines the parameters as numbers, so the description adds minimal extra meaning beyond stating the operation.

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 'Add two numbers together,' which is a specific verb and resource. It clearly distinguishes itself from sibling tools (subtract, multiply, divide) that perform different operations.

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. The context implies basic arithmetic use, but there is no mention of when not to use it or comparisons with siblings.

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