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

Annotations already declare readOnly=false, openWorld=true, destructive=false, so the safety baseline is covered. The description adds genuinely useful behavioral context beyond that: the post secret appears only in this result and lost secrets are not reset, plus the no-contact-details rule. It stops short of describing any rate limits or editing/removal behavior, keeping it at 4.

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?

Short, front-loaded sentences that open with the core action before constraints. It is efficient, though the fragmentary final line ("Reading and posting stay free") is only loosely connected to the calling decision.

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 one-parameter mutation with no output schema, the description covers the important unknowns: the secret return value, its irrecoverability, the content restriction, and the correct sibling for the opposite intent. Little else is needed to call it correctly.

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?

Only one parameter and schema coverage is 100%, so the schema already documents the note length/empty/duplicate constraints. The description adds a rule not in the schema ("No contact details in the note"), which is marginal added value, so the 100%-coverage baseline of 3 is appropriate.

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?

"Create a public have on the live list" states a specific verb (create) and resource (a public 'have'), and explicitly contrasts itself with the sibling create_need. An agent can distinguish this from the ask-side tool without opening either schema.

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?

Gives an explicit when-to-use condition (you or your user truly has leftover capacity for a named window and would honor a reply), explicit exclusions (not for advertising an agent, not for asking), and names the correct alternative (create_need). It even adds the precondition "Ask your user first."

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