summarize

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

Annotations already declare readOnlyHint=true, and the description adds meaningful context beyond that: local model execution, map-reduce strategy, megabyte-scale capability, preservation of concrete details, and that the full summary is saved to a file. It doesn't describe failure modes or timeout behavior, but the added operational context is substantial and does not contradict annotations.

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 purpose and capability, then usage guidance, parameter hints, and a closing exclusion. Dense but every sentence earns its place; slightly long but efficient given the 4 parameters and 0% schema coverage it must compensate for.

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?

Complete for a read-only summarization tool: purpose, when/when-not, parameters, and a behavioral note about saved output. The main gaps are undocumented timeout_s and no explicit statement of what the tool returns directly (no output schema exists), which an agent would need to know. Minor against an otherwise thorough definition.

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?

With 0% schema description coverage, the description carries the full burden and documents 3 of 4 parameters: paths (absolute), text (inline), and question (with a concrete example). It omits timeout_s entirely, which is a gap, but the parameters it does cover include usage context beyond the schema's bare names.

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 ('Summarise') + resource (large files, logs, text) with an explicit mechanism (LOCAL models, map-reduce). Clearly distinguishes from siblings by naming 'Read' as the alternative and scoping to long files, which separates it from search_code, index_codebase, and review_diff. The purpose is unambiguous.

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?

Explicitly states when to use (long files needing gist or a specific question answer) and when not to use ('NOT for short files (<200 lines): just Read them'), naming the exact alternative tool. Gives a concrete example question. This is as explicit as usage guidance gets.

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