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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so safety is fully covered. The description adds that the whole chapter text is returned rather than excerpted, but says nothing about truncation, size limits, or what happens if a chapter id is invalid. Modest value on top of structured fields, hence a 3.

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?

One sentence, front-loaded with what is returned before the accepted input forms, with no filler. It reads slightly compressed ('by chapter id ... or chapter number'), but nothing is wasted.

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 one-parameter read tool with full schema coverage, rich annotations, and no output schema, the description covers what the tool returns and how to obtain the identifier. The remaining gap is minor: no mention of error behavior for unknown chapter ids.

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%, and the single schema field already documents both accepted forms ('ch03-twr' or '3'). The description restates exactly that ('by chapter id ... or chapter number') without adding format, case-sensitivity, or fallback behavior, so it lands at the baseline for a fully documented schema.

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 resource and scope: the full text of a single textbook chapter, keyed by chapter id or number. It also distinguishes itself from search_textbook by crediting it as the source of chapter ids. The action verb is only implied (the title supplies 'Read'), which keeps it just short of 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?

'by chapter id (from search_textbook) or chapter number' establishes a clear workflow: discover ids via search_textbook, then fetch full text here. It does not state any when-not conditions or note that search_textbook should be preferred for topical lookups, so the routing guidance is one-directional rather than complete.

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