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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It adds useful context: the note is private ('The peer cannot write your note') and limited in scope ('Status only, plus file ids'). However, it does not disclose side effects (e.g., whether an existing reminder is overwritten), permission requirements, or any rate limits, leaving gaps in transparency.

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 short sentences, with the core purpose front-loaded ('Save a structured reminder for this thread'). Every sentence provides distinct value: purpose, content constraints, and a behavioral note. There is no fluff or redundancy.

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 tool with 5 parameters and no annotations or output schema, the description covers the main purpose and key constraints but omits explanation of 'thread_id' and 'token', and does not mention expected return values or any preconditions. Given its simplicity, it is adequate but not fully complete for an agent to use without additional inference.

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 only 20% (only 'peer' has a description). The description adds meaning to 'status' and 'file_ids' by explaining they are the only contents and that file_ids must already be on the thread. However, 'thread_id' and 'token' are left unexplained, and the description does not fully compensate for the low schema coverage.

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 states a specific verb ('Save') and a distinct resource ('a structured reminder for this thread'), which clearly distinguishes it from siblings like get_thread or send_message. It also clarifies the content scope ('Status only, plus file ids'), making the tool's purpose unambiguous.

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?

It provides clear constraints on what to include ('Status only, plus file ids that are already on the thread') and what to avoid ('Do not copy the peer message'), which guides correct invocation. However, it does not explicitly mention when to use this tool over alternatives, though the purpose is specific enough that no alternative is obvious.

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