read_wiki

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

Annotations only declare readOnlyHint=true, so the description carries most of the burden and delivers real operational context: pages can be fresh or stale, what made them stale, and that a stale page describes code that has changed and its citations should be checked. It also discloses the citation payload shape (repository, path, line range). Some of the return detail overlaps the existing output schema rather than adding new behavioral information, which keeps it just below the top score.

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?

Purpose is front-loaded, then read-mode behavior, then list-mode behavior, then next step — a logical order with each sentence doing work. It is longer than necessary for a two-parameter tool, and the return-value paragraph partly duplicates the output schema, but nothing is 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 read-only lookup tool with full schema coverage, annotations and an output schema, the description supplies everything an agent needs to choose it, pick a mode, and interpret staleness. The one remaining gap — pagination or size limits on listings — is minor and not implied by the schema.

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 baseline is 3; the description goes beyond the schema by framing the two modes (pass page to read one page, omit it to list) and by stating that listing can be scoped to one repo with name, state and first purpose line. It adds no syntax or format nuance beyond what the parameter descriptions already say, so it sits modestly above baseline.

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 ("Reads the tool's wiki page about a module") and immediately glosses the resource ("a directory of indexed code") so the domain concept is unambiguous. It also distinguishes the tool from its nearest sibling: use it for a module as a whole "rather than one function" (get_symbol), which lets an agent route correctly 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?

Gives an explicit trigger (question about a module as a whole, or after search_code returns a hit of kind page), an explicit alternative (get_symbol for a single symbol), and a prescribed next step (get_symbol on a key symbol). The omit-page-versus-pass-page branch is stated in prose, so both invocation modes are covered.

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