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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the description's job is to add operational context — it discloses the return fields (title_id, title_text, page_id, has_children), the two-mode behavior, and depth recursion semantics. It stops short of discussing pagination or large-book limits, so it is strong but not exhaustive.

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?

Front-loads the purpose, then modes, then return shape, then examples — a clean information hierarchy. Slightly long because it carries two examples and a mode enumeration, but each sentence earns its place. The duplicated Arabic title line is minor padding.

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?

No output schema exists, so the description carries the return-value burden and does so by enumerating the per-entry fields. Combined with dual-mode explanation, id-lookup guidance, and downstream usage, an agent has everything needed to invoke and interpret this 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 coverage is already 100%, so the baseline is 3, but the description adds cross-parameter semantics the schema cannot express — that parent_id=0 means top level, that depth 1–5 controls tree recursion, and that containing_page_id switches modes entirely. Worked examples with concrete values reinforce this.

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 ('Fetch a downloaded book's table of contents') and explicitly distinguishes itself from sibling shamela_get_book_section, which it routes users to for reading the section. An agent can tell what this returns without opening the 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?

Gives explicit modes with the conditions that select each: subtree mode (default, via parent_id/depth) vs ancestor-chain mode (via containing_page_id). It also names the alternative tools for finding book ids (shamela_list_downloaded_books, shamela_resolve) and the downstream consumer (shamela_get_book_section).

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