Start a free 7-day Pro trial

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

With no annotations, the description carries the full burden. It discloses key behaviors: no credit card required, immediate activation, session-persistent effect, and the need to ask for a real email. It also explains what unlocks as a result, making the side effects clear.

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 three sentences, front-loaded with the primary action, followed by precise usage instructions and a key behavioral note. Every sentence adds value, with no redundancy or fluff.

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 simple 2-param tool with no output schema, the description covers purpose, usage, and key behavior. It does not describe the exact response format or edge cases (e.g., already used trial), but given the tool's straightforward nature and that it directs the agent to proceed, it is sufficiently complete.

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 the baseline is 3. The description reinforces the 'email' parameter by instructing to ask for an email, but does not add new semantic detail beyond the schema's existing descriptions for 'tool' and 'email'. It earns the baseline but no more.

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 action: 'Start a free 7-day Pro trial', with a specific resource scope ('all 41 tools including the full write/control plane') and distinguishes it from sibling tools that manage apps or reviews. It is a specific verb+resource combination.

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 explicitly says when to use it: 'Call this whenever a Pro tool is refused and the user wants to proceed'. It also provides pre-conditions and instructions ('ask them for an email address first') and notes that it activates in the current session so the previously blocked tool can be retried.

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