Decode a vector ID

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

With no annotations, the description bears full responsibility for behavioral disclosure. It only says 'Returns' which implies a read-only operation, but it omits information about authentication, error handling, rate limits, or exact response format. This is a significant gap for a tool with no annotation safety signals.

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 one sentence preceded by a clarifying rhetorical question, providing all necessary information without any fluff. It is concise, front-loaded, and effectively communicates the tool's purpose.

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?

Given the tool's simplicity (single parameter, no output schema), the description adequately names the return fields (series title, source table, coordinate). It lacks details on error behavior, but for a straightforward lookup tool, the provided context is nearly 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?

The input schema already documents the vector parameter with type ('string' or 'number') and an example ('v41690973' or 41690973). The description adds little beyond repeating that it takes a vector ID. With schema coverage at 100%, the 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?

The description clearly states what the tool does: 'Returns the series title, source table, and coordinate for a vector ID.' This is a specific verb plus resource, and it distinguishes from sibling tools by focusing on decoding a vector ID rather than searching tables or fetching data.

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 informal question 'What is this vector?' implies use when you have a vector ID and want to identify its series. However, there is no explicit guidance on when not to use it or which sibling tool to use instead, leaving the context to be inferred.

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