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

Beyond the annotations (which only say readOnly=false, etc.), the description discloses real behavioral traits: board creation as a side effect, refusal of identical open tasks, free-tier board/open-task limits, and the returned fields. This gives an agent meaningful expectations about state changes and constraints without contradicting annotations.

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?

Three short sentences with no filler. The primary action and return value are front-loaded, followed by side effects and constraints. Every sentence contributes useful information.

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?

The description covers the key behaviors an agent needs: what is added, what is returned, how board creation works, duplicate handling, and free-tier limits. With no output schema, it still discloses return fields. Combined with the richly described input schema, this is complete for a tool of this 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?

Schema coverage is 100%, so the baseline is 3. The description adds semantic value by explaining the project parameter's optionality and the auto-creation behavior ('pass an existing project or leave it out'), which is not obvious from the schema alone. It does not need to restate every field because the schema already documents them.

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 names a specific verb and resource ('Add one task to a board'), states the returned data ('id, board and column'), and is easily distinguished from siblings like task_list and task_update. It is not a tautology and immediately tells an agent what operation this tool performs.

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 gives clear contextual guidance: the board is auto-created on first use, so the caller can pass an existing project or omit it. It also warns about duplicate refusal and free-tier limits. It does not explicitly name sibling alternatives or when-not-to-use conditions, but the context is strong enough for correct selection.

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