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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description adds real value beyond that by disclosing the return format (full text as Markdown) and the slug provenance, though it says nothing about behavior for a missing slug, truncation of long posts, or per-language variation.

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 tight sentence with the resource and output format front-loaded and the slug dependency trailing. Every clause earns its place; nothing is padding.

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?

For a two-parameter read tool with no output schema, the description covers what is returned (full post text as Markdown) and how to obtain the required slug, which is enough to call it correctly. Missing only edge-case behavior such as a nonexistent slug or oversized posts.

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%, with both slug and the language enum fully documented and defaulted in the schema. The description only restates 'by slug' and never mentions the language parameter, so it adds nothing beyond the schema baseline.

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 ('the full text of one blog post'), the lookup key ('by slug'), and the output format ('as Markdown'). It also distinguishes itself from the sibling search_posts by naming it as the source of the slug, so an agent can separate lookup-by-slug from browsing.

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?

The parenthetical '(from search_posts)' explicitly routes the agent to the sibling that produces the required slug, giving clear preconditions. It stops short of stating when NOT to use this tool (e.g. use search_posts/get_post listing for discovery), so no explicit exclusions.

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