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

Annotations already cover read-only, idempotent, non-destructive and open-world. The description adds genuinely new behavioral context — the credit cost ('Flat 5 points per successful run') — but says nothing about whether the tree is returned in full or truncated by max_items, nor about paging.

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 with zero filler; the payload contents lead and the cost note follows. Nothing to trim.

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 does list the returned fields, which is helpful. But for a 4-parameter, tree-traversal tool it omits how level/parent_id interact with max_items and whether results are a full tree or a bounded slice.

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 domain enum with country mappings and max_items bounds, so the schema carries parameter meaning. The description adds nothing about what 'level' or 'parent_id' do, and its phrase 'full category tree' slightly undersells that the call can be scoped to a subtree.

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+resource ('Full category tree of an OLX marketplace') and enumerates returned fields, so the agent knows exactly what it gets. It does not name or contrast with the closely related siblings (run_olx_categories_filters, run_olx_regions), which would be needed for a 5.

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?

No statement of when to use this versus run_olx_categories_filters (which presumably adds filters) or the per-domain alternatives. The agent must infer that this is the discovery/enumeration step before run_olx_offers_search.

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