pack_context

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

With readOnlyHint=true already covering safety, the description adds genuine behavioral detail: it groups contiguous chunks by file, dedupes, and trims to strict token budgets. This discloses the transformation logic an agent needs to predict the output, though it says nothing about ordering or failure/shortfall behavior.

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?

Two dense sentences with zero filler, front-loading the primary action and packing the grouping/dedupe/trimming behavior efficiently.

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?

An output schema exists, so return values need not be described. However, with six parameters at 0% schema coverage and no parameter explanations, the definition is incomplete for correct invocation despite a solid behavioral summary.

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 0% and six parameters exist, so the description carries the full burden. It only hints at max_tokens via the 'e.g. 4000 tokens' example; alpha, rerank, path_glob, include_line_numbers, and query are entirely unexplained, leaving most parameters undocumented in both schema and description.

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?

The description states a specific verb ('Assemble') and resource ('Markdown prompt context pack from search hits'), and its output nature (packed context) is distinct from the search/retrieval siblings. It stops short of naming a sibling to differentiate against, but 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?

Usage is implied by 'from search hits', suggesting it operates downstream of search, but there is no explicit when/when-not guidance or named alternative among the many search-related siblings. The agent must infer the workflow position.

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