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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, openWorldHint, destructiveHint=false). The description adds real behavioral context beyond them: only public FirmTape documents are reachable, and long pages are truncated with a link to the remainder. It does not mention auth requirements or rate limits, so it falls short of 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?

Front-loaded with the core action, then compactly sequenced as accepted inputs, use-when, not-for, and limits. Every clause carries routing or constraint information; there is no filler.

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-parameter read tool with no output schema, the description covers the return nature (full text prose), the truncation edge case, the input formats, and the routing decision against siblings. Nothing needed to call it correctly is missing.

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 schema already names the three accepted id kinds, so baseline is 3. The description goes further by explaining the prefix conventions (`session:YYYY-MM-DD`, `page:/path`) and that a bare date or URL also works, giving the agent format-level meaning the schema does not.

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 ('Retrieve the full text of one FirmTape document') and immediately names the id namespace that identifies the document. It explicitly distinguishes itself from get_session and get_levels, so an agent can route without opening any 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?

Provides explicit 'Use when' (you hold an id from `search`, or a client that only speaks search/fetch) and 'Not for' clauses naming the alternative tools that return structured numbers instead of prose. Both the selecting condition and the exclusion are stated.

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