Find the blocks that hold some text

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

Annotations only declare readOnlyHint and openWorldHint, so the description carries the real burden and does it well: substring/case-insensitive matching semantics, the innermost-block address rule, deduplication of multi-line matches, the default search scope (`*.geml` and `*.md` under the root) versus a named file searched regardless of extension, and the important fact that no match is an empty result rather than an error.

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?

Every sentence earns its place and the output format, sibling contrast, and matching rules are front-loaded. The em-dash asides make individual sentences long and slightly dense to parse, which costs a point but not readability overall.

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 still specifies the return shape precisely (tab-separated file/address rows, plus the optional third column behind `head`) and the empty-result case. For a 5-parameter read tool with annotations covering safety, nothing an agent needs 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%, so the baseline is 3, but the description adds genuine meaning: it fixes matching semantics for `pattern` (substring, case-insensitive unless `case` is true), pins the default and the file-vs-directory behavior of `path`, and explains that `within` shares geml_get's `id` selector forms. That is more than restating the 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?

States a specific verb and resource ('Search block CONTENT across the served documents') and immediately defines the output shape ('each hit is one `<file>\t<address>` row'). It explicitly distinguishes itself from the sibling geml_list ('geml_list says what a document contains, this says which block holds the words'), so the agent can route 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?

Names the alternative tool (geml_list) and the condition that selects this one, and points the agent onward by noting the address 'pastes straight into geml_get or geml_set'. It does not cover when to prefer this over non-search siblings like geml_check or geml_history, nor state any exclusion beyond that single contrast.

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