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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds that the result includes a public profile plus recent articles, but says nothing about pagination, recency window, or result limits. An output schema exists, so return detail is not required, making a 3 appropriate.

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 filler, and the core capability is front-loaded before the sibling routing in the second sentence.

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 single-required-param read tool with annotations covering safety and an output schema covering returns, the description is nearly complete; the only absent detail is result scope (e.g., how many recent articles are returned), which is minor given the output 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 coverage is 100% and the parameter itself documents 'Canonical scmp.com/author/<slug> URL'. The description repeats the canonical-URL requirement but adds no format or edge-case detail beyond the schema, which is the expected baseline when the schema does the work.

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 (Fetch), resource (SCMP author's public profile and recent articles), and access method (canonical author URL). It also names the two sibling tools it is not, so an agent can distinguish it from scmp_article and scmp_headlines without inspecting schemas.

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?

Routes the agent explicitly to scmp_article for a single story and scmp_headlines for current headlines, which is clear context on the alternatives. It stops short of an explicit 'when to use this tool' trigger, but the routing is unambiguous for a one-param lookup.

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