set_message_reminder

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

Annotations already declare readOnlyHint=false (mutating), idempotentHint=true, and destructiveHint=false. The description adds genuinely useful context beyond these: 'Replaces an earlier reminder' explains the idempotent overwrite semantics, and 'Must be in the future' is a hard validation constraint not encoded anywhere else.

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?

Front-loaded purpose sentence, then tight Args and Returns sections with no filler. Every sentence contributes information an agent needs to call the tool correctly.

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?

All three required parameters are documented, the future-time validation and format are stated, and overwrite semantics are disclosed. An output schema exists, so the additional Returns block is a minor bonus rather than a necessity, and nothing needed to invoke the tool correctly is missing.

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 0%, so the description carries the full burden and does so well: it defines token as 'The conversation token,' message_id as 'The message to be reminded about,' and remind_at with an explicit ISO 8601 format and timezone example plus a future-time constraint.

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?

States a specific verb+resource ('Have Talk remind you about a message later with a notification') and distinguishes scope ('a message') from the similarly-named set_file_reminder sibling. Also surfaces the replacement semantics, so an agent can identify it without opening the 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?

Usage is implied by the purpose ('remind you about a message later'), and it notes it 'Replaces an earlier reminder,' which clarifies it is an upsert rather than an additive create. However, it names no alternative or when-not-to-use condition, and does not point to remove_message_reminder or list_message_reminders for the related lifecycle operations.

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