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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is fully covered by structured data. The description adds only that the return is full text (as opposed to the abbreviated results search yields), which is modest extra context; it says nothing about error behavior for bad ids or rate limits.

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?

A single front-loaded sentence with zero filler; the id format appears immediately rather than buried. It is terse to the point of being a fragment, but every element 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?

There is no output schema, and the description covers the essential return nature ('full text') plus the input grammar, which is adequate for a one-parameter read tool with complete annotations. Minor gaps remain around invalid-id behavior and whether any metadata accompanies the text.

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 0%, so the description carries the whole burden for the single id parameter, and it does so well by giving the concrete id grammar with examples ('listing:<uuid>', 'project:<slug>'). It stops short of saying where the id originates beyond 'a result from search', but the format detail is genuinely useful beyond the bare 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?

The description states a concrete resource and scope: it returns the full text of a document that came from search, and the title names the verb (fetch a Heimster document). It is a noun phrase rather than a verb+resource sentence, and it never contrasts itself with siblings like get_listing or search, so it is clear but not fully differentiated.

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?

Phrasing as 'a result from search' implies the intended pipeline (call search first, then fetch with a returned id), which is useful implied usage. However there is no explicit when-to-use/when-not guidance and no statement of how it differs from get_listing, so usage must be inferred.

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