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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower; the description still adds real value by disclosing that results are ranked by lexical relevance only, never by payment, and that an earlier call is not required. It also pre-empts a likely misreading by stating the output is 'no decision'. It does not discuss pagination or result-set limits beyond the schema.

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?

Dense but tightly organized into purpose, Use when, Not for, Input, and Output blocks, with the core action front-loaded. A few phrases are redundant with the schema (the 500-character restatement), but nothing is truly wasted.

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 present, the description compensates by naming the return type (ak.search.v1) and its fields, and it closes the loop by stating no decision is produced. Combined with the explicit routing guidance, an agent has everything needed to select and invoke this tool correctly.

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 100%, so query and limit are already documented in structured form; the description largely restates the 500-character query constraint and adds only the useful note that no prior call is needed. The limit parameter is not mentioned in the description at all. Baseline 3 is appropriate when the schema carries the parameter burden.

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 (Search) and resource (capability names, summaries, tasks, use-when conditions) with a stated ranking rule. It explicitly distinguishes itself from named siblings get_capability, resolve_task, and evaluate_capability, so an agent can route 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?

Contains explicit 'Use when:' and 'Not for:' clauses, each with the alternative tool to call instead (resolve_task, evaluate_capability, get_capability). The condition that selects this tool versus its siblings is fully spelled out.

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