Study another writer's posts

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

Annotations already cover readOnly/idempotent/openWorld, but the description adds real value beyond them: it discloses that output is third-party text and warns to treat it as content, not instructions (an injection-safety note). It also clarifies the returned metrics. It omits auth/permission or pagination behavior, so not a 5.

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 action and tightly organized into purpose, usage, and a safety caveat. There is mild redundancy with the schema (the sort advice is repeated) but every sentence otherwise earns its place.

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 appropriately names what is returned (likes, comments, restacks) and adds the safety caveat plus scope. For a 3-param read tool this is nearly complete; only minor gaps like pagination or cross-publication limits remain.

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 description coverage is 100%, so all three parameters (including the sort_by enum) are already documented in the schema. The description's "sort by likes or restacks to find their best work" largely restates the schema's own sort_by guidance rather than adding new syntax or constraints, so the baseline 3 applies.

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 ("Pull") and resource ("another publication's recent posts") and enumerates the engagement fields returned (likes, comments, restacks). "Works on any Substack, not just your own" scopes it against the caller's own-tools like list_posts, though no sibling is named explicitly, which keeps it from a 5.

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?

"Use this to see what actually landed for someone rather than what they published most recently" gives clear intended usage and even frames the date-vs-engagement tradeoff. It stops short of naming alternatives (e.g. research_creator_notes, compare_publications) or stating exclusions, so it does not reach a 5.

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