Check DTU Learn connection

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

Annotations already declare readOnly, idempotent, non-destructive, and open-world, so the safety profile is covered. The description adds value beyond that by disclosing the return content in plain terms (whether you are signed in, and as whom) and by positioning it as a diagnostic step, though it says nothing about failure modes or output shape beyond that.

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?

Two sentences, zero waste: the first defines the behavior and the second gives the routing rule. The most actionable guidance (use first on auth errors) is placed last but follows immediately from the purpose statement.

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 zero-parameter, read-only diagnostic with full annotation coverage, the description supplies everything an agent needs: what it returns conceptually and when to reach for it. No output schema is needed since the return is described in one clause.

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 tool takes zero parameters, which is the baseline-4 case; there is nothing to misinterpret. The description correctly implies a no-argument call by framing it as a pure status check.

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 and resource: checks DTU Learn sign-in state and reports the signed-in identity. It implicitly separates itself from the sibling `login` tool (read a status vs. perform a sign-in), though it never names that sibling, so differentiation is inferred rather than stated.

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?

"Use this first if other tools report authentication problems" gives a concrete trigger condition for selecting this tool. It stops short of explicitly naming `login` as the follow-up alternative when the check fails, but the context is clear enough to act on.

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