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

With no annotations, the description carries the full disclosure burden but only mentions the action and return value. It does not disclose persistence side effects, alias-conflict behavior, permissions, or failure modes, which matter for a creation tool.

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?

A single sentence that front-loads the core action and outcome with no filler. Every word contributes to understanding what the tool does and what it returns.

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 3-parameter tool, the description covers the core purpose and gives a hint of the output. However, with no output schema, the mention of 'stats' remains vague, and service-specific constraints or error behaviors are absent.

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 coverage is 100%, so the description does not need to restate parameters; it also does not add semantics beyond what the schema already provides for destination_url, alias, and title. The baseline 3 is appropriate because the schema handles parameter documentation.

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 concrete verb ('Shorten'), a specific resource ('destination URL'), a service ('Surli'), and an expected result ('short link and stats'). This clearly distinguishes it from siblings like get_short_link and update_alias/update_destination, which retrieve or modify rather than create.

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 implies use when a new shortened URL is needed, and the create/read/update contrast with siblings gives some context. However, it never explicitly says when to prefer this tool over get_short_link or update_alias/update_destination, and it offers no exclusions.

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