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

Annotations already declare readOnly, idempotent, closed-world and non-destructive, so the safety profile is fully covered without the description. The description adds only the shape of the return (description, input schema, safety flags) and the pre-first-call timing, and says nothing about behavior on unknown tool names or the opt-in _meta forwarding that the schema mentions. Adequate but thin given how much the annotations already carry.

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 short sentences, zero waste. The returned content is stated first and the usage rule second, so the reader gets both the what and the when at a glance.

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 two-parameter lookup with no output schema, describing the payload (description, input schema, safety flags) effectively covers the return value, and the usage rule is supplied. Minor gaps: behavior for a nonexistent tool name and the analytics caveat in _meta are left entirely to the schema.

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%, including the note that the name must be exact and comes from search_tools or list_toolsets. With the schema doing the heavy lifting, the baseline of 3 applies; the description adds no meaning about the name argument or the _meta analytics object.

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 names a specific verb and resource — it returns the full definition of one tool (description, input schema, safety flags). That's clearly distinct from passing arguments to a tool, but the siblings (search_tools, list_toolsets, call_tool) are never named, so the differentiation is left implicit.

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?

It gives a concrete trigger: read it before the first call of a tool whose definition you don't yet have, so arguments are correct. That's a clear when-to-use rule. It stops short of saying when to skip it (e.g., when you already have the definition) or naming search_tools as the recommended preceding step, though the parameter schema does supply that routing.

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