DAR connection status

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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint=false, so the safety profile is covered. The description adds genuinely non-obvious operational context: the REST sunset date of 2027-01-15 and what changes after it, plus the CC BY 4.0 attribution obligation. It stops short of stating latency expectations or failure modes, but the added value over annotations is substantial.

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-loads the action, then a structured 'Returns:' list of the four reportable facts, then a 'Use first when...' routing sentence. Every sentence carries distinct information with no repetition of the title.

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?

With no output schema, the description must enumerate what comes back, and it does — REST reachability and latency, API-key configuration, sunset date, and attribution text. That is exactly the information an agent needs to interpret the response and act on it.

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, so the baseline of 4 applies per the rubric. There is nothing for the description to clarify about inputs, and it correctly spends no words on parameters.

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 — check connectivity to DAR and report which access paths are configured — which is clearly a diagnostic/status operation distinct from the data-retrieval siblings (dar_get_address, dar_list_addresses, etc.). An agent can identify this as the health-check tool without opening any 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?

Gives explicit trigger conditions ('Use first when a DAR call fails unexpectedly') and a concrete decision use case, naming the sibling dar_search_addresses and the prerequisite (needs API key) that this tool answers. Both when-to-use and which-alternative-is-affected are spelled out.

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