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

Annotations only cover readOnlyHint, so the description carries most of the behavioral burden and does it well: it discloses that the result is a single entity with both the raw `spec` and compiled `built_spec`, and even names the backing source (`live_specs_ext`). It stops short of describing not-found behavior or whether the spec is live vs draft, which is the only real gap.

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?

Purpose is front-loaded in the first clause, followed by the return contents and then implementation detail. Three tight sentences with no wasted preamble, though the PostgREST/table identifiers are arguably implementation trivia an agent rarely needs.

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 usefully enumerates the returned fields (`spec`, `built_spec`) and the readOnly annotation covers the safety profile, so an agent has enough to call it correctly. Missing only edge-case behavior such as error/empty responses for a non-existent catalog_name.

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% and the parameter already documents the exact-match format with an example, so the baseline is 3. The description reinforces exactness via the `catalog_name=eq.<name>` and `limit=1` query fragment, but that adds little beyond what the schema already states.

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 ('Get one live catalog entity'), names the keying parameter (catalog_name), and specifies what it returns (serialized `spec` and compiled `built_spec`). This clearly separates it from the sibling `estuary_list_catalog` and `estuary_get_catalog_stats`, so an agent can route correctly without opening a schema.

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 phrase 'by its exact catalog_name' implies you must already know the identifier, which is useful context, but there is no explicit when-to-use vs `estuary_list_catalog` (discovery) or `estuary_get_catalog_stats`, and no statement of what happens if the name is not found. Usage is implied rather than guided.

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