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

Beyond annotations (readOnlyHint, openWorldHint), the description discloses a real operational trait: calls can take up to ~50 seconds and may fail with a retryable 503. That is exactly the kind of context annotations cannot carry. It stops short of covering rate limiting or how pagination interacts with the API's 50-page cap, so not a 5.

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?

Four short sentences, zero filler: purpose first, then the slug dependency, then the alternative-tool routing, then the latency/failure caveat. Each sentence earns its place.

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 an output schema present, the description needn't enumerate fields, and it doesn't over-explain. It covers the slug dependency, the sibling alternative, pagination signals, and the slow/flaky behavior. Minor gap: it doesn't say what an agent should do on a 503 beyond implying retry.

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%, so country and category are already documented, including that the slug comes from jumia_categories. The description's note about sourcing the slug largely restates the schema. Baseline 3 is appropriate — the schema does the heavy lifting.

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 ('Browse one Jumia category listing by slug') and pins down the return shape (same product cards as jumia_search plus total_count and has_next). It also names the sibling (jumia_search) it is not, so an agent can distinguish the two without opening either 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?

Explicitly routes the agent: take the slug from jumia_categories, and use jumia_search for keyword queries. Both the prerequisite and the alternative tool are named with the condition that selects them.

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