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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower. The description adds real context beyond them: the words are a machine transcript rather than a checked line, the units returned are 'moments', and query syntax (quoted phrases, leading minus) is supported. It does not state result-count limits or failure modes.

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 core purpose and search scope, then layers return shape, a quotability caveat, and syntax support. Dense with parentheticals but every sentence carries information; 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?

With no output schema, the description takes on the burden of describing returns and does so concretely (source, startSeconds/endSeconds, snippet with «» markers, moment link, yankThisPartUrl). Combined with the annotation-covered safety profile and the transcript caveat, an agent has enough to call and interpret the tool.

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 50% (query is documented, limit is bare), so the description must compensate. It adds genuine meaning by describing query syntax (quoted phrases, leading minus) beyond the schema's simple 'words or quoted phrase' note. It still says nothing about the limit parameter.

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 (full-text search over full transcripts of every podcast/video) and explicitly scopes it apart from the sibling concern ("not only their five lines", i.e. search_lines). An agent can distinguish it from search_lines and get_lines_for_url without opening a 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?

Routes the agent for the quoting case explicitly ("to quote one, yank that part or use check_quote"), and the contrast with the five-lines tool implies when search_lines is the wrong choice. There is no explicit statement of when to prefer search_lines or get_yank, so it stops short of full when/when-not guidance.

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