bluesky-mcp-server

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, so the description carries the full burden of behavioral nuance beyond that. It discloses that all filters include reposts, explains the 'repostedBy' and 'author' fields, warns that 'limit' counts reposts so the returned page may hold fewer original posts than expected, and mentions cursor pagination. This is rich, actionable context that significantly aids invocation.

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?

The description is long but every sentence carries essential information—behavioral traits, return fields, filter semantics, and a critical caveat about pagination count. It is front-loaded with the core action and logically progresses through details. There is no redundancy, and the structure makes it easy to scan.

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?

Given the tool's complexity (4 parameters, an enum filter, behaviors around reposts and limit, pagination) and the presence of an output schema, the description covers all necessary context: what is returned, the meaning of key fields, the limitation of filters regarding reposts, and the pointer to bsky_get_post_thread for deeper drilling. Nothing an agent needs to call it correctly is missing.

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 parameters are already documented. The description adds meaning beyond the schema by clarifying the practical implication of 'limit' (it counts reposts, so use 'originalPosts' from the enrichment fields for the actor's own writing) and by reinforcing that no filter excludes reposts. This elevates the semantics beyond the baseline for full schema coverage.

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 opening sentence states a precise verb, resource, and ordering: 'Get a Bluesky user's recent feed ordered newest-first.' It clearly distinguishes itself from siblings by referencing bsky_get_post_thread for thread drilling and by its focus on a single author's feed rather than search or follows. No ambiguity about what the tool does.

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 description explains when to use the tool (fetching a specific author's feed) and implicitly differentiates it from siblings through its focus and the mention of bsky_get_post_thread for threads. It does not explicitly list exclusions or alternative tools for other use cases, but the context is clear enough that an agent can select it appropriately.

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

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

Annotations already carry readOnlyHint, openWorldHint, and idempotentHint, so the safety profile is covered. The description adds genuine behavioral context beyond that: the response shape (paginited actor profiles with listed fields plus a subject summary), the explicit exclusion (website not on this view), and the pagination caveat ('large social graphs return only the first page; use cursor pagination'). This meaningfully helps the agent call it correctly.

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 sentences that front-load the core purpose before the returns and caveats, with no filler. The pagination caveat and the website exclusion each earn their place, though the sentence carrying response details is slightly dense, packing fields, the summary, and the exclusion into one clause.

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 read-only, paginated list tool with a 100%-documented schema, an output schema, and safety annotations, the description is nearly complete: purpose, return fields, pagination behavior, and an exclusion are all present. Rate-limit or error behavior isn't mentioned, but that is a minor gap given the annotations and output schema already supplied.

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 every parameter (actor, limit, cursor, direction) is already documented in the input schema, including the actor handle/DID distinction and the direction enum explanation. The description adds only the return-field context, not parameter details, so baseline 3 is correct — the schema does the heavy lifting.

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 ('Fetch'), a precise resource ('social graph edges for a Bluesky account'), and a clear scope ('who follows them, or who they follow'). It actively distinguishes itself from a sibling by noting 'website is not on this view, only on bsky_get_profile', so an agent can tell it apart from bsky_get_profile without opening either 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 description gives clear functional context for when to call it (fetching followers/following) and an explicit redirection: if website data is needed, use bsky_get_profile. The schema further routes bare-name lookups to bsky_search_actors. It lacks a broader when-to-use vs. not statement, but the sibling differentiation is concrete and useful.

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

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, and the description is fully consistent with all three. Beyond that it discloses substantial non-obvious behavior the annotations cannot express: per-post reply limits with 'truncated: true', the two 'truncationReason' values (depth/unavailable) and their differing implications, 'unreturnedReplies' as an upper bound rather than an exact missing count, 'parentChainTruncated' semantics, and the author-heading indentation convention. This far exceeds what structured fields provide. No contradiction with annotations.

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?

The description is long and dense with well over ten sentences, which risks over-specification—but nearly every sentence earns its place by explaining genuinely non-obvious truncation and continuation semantics that no schema field could convey. The purpose is front-loaded in the first sentence, and the rest flows logically from thread structure to truncation markers to counter-semantics caveats to formatting. It is verbose yet information-dense; only the redundancy around continuation ('fetch its AT-URI as its own thread' appears several times) prevents a 5.

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?

Given the output schema exists (so return-value details needn't be restated) and the high complexity of this tool—asymmetric truncation, parent-chain cutoffs, counter semantics, hidden indentation—the description is remarkably complete for correct invocation and interpretation. It covers tool selection, parameter provenance, truncation detection, continuation strategy, the caveat about unreturnedReplies being an upper bound, and even the rendering convention for reply depth. Nothing an agent needs to call and interpret this tool correctly is missing.

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 100%, so the schema already documents all three parameters (uri, depth, parent_height) in depth—this sets the baseline at 3. But the description adds genuine value beyond the schema by explaining how depth and parent_height interact with truncation: depth does not widen the reply tree, the per-post reply limit is independent of depth, and the continuation strategy is a consequence of these bounds. It explicitly names how to obtain the uri ('returned by bsky_search_posts and bsky_get_author_feed'), which is not in the schema. This compensates beyond 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?

The opening sentence is a specific verb+resource—'Fetch the conversation for a post by AT-URI'—with an immediate scope statement (parent chain upward, reply tree downward) that distinguishes it from siblings. It also explicitly ties the AT-URI source to bsky_search_posts and bsky_get_author_feed, making the separation from those siblings explicit. No ambiguity about what this tool does.

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 description gives clear, actionable guidance: enter at any thread point, and readers can traverse deeper by fetching an edge node's AT-URI as its own thread when truncation markers appear. It also names the sibling sources of the AT-URI parameter. It stops short of an explicit 'when NOT to use this vs. bsky_search_posts' contrast, but the traversal and continuation instructions are concrete and well-motivated, which earns it above the 3-level implied-usage baseline.

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

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, covering safety. The description adds value by detailing the exact return contents (profile fields, moderation labels, pinned post AT-URI) and noting the public nature of the data. No contradiction with annotations.

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?

The description is front-loaded with the core purpose and returns a useful list of fields. It is slightly redundant (e.g., 'Handles and DIDs are interchangeable as input' duplicates the schema) but remains compact and structured.

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 single-parameter read tool with an output schema available, the description covers the input format, usage context, return values, and resolution workflow. Nothing an agent needs to call it correctly is missing.

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 already explains the handle/DID formats and the note about bare names. The description repeats this without adding new parameter-specific meaning, so it stays at the baseline for high schema coverage.

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 clearly states the tool fetches a public profile by handle or DID and enumerates the returned fields (displayName, handle, DID, bio, counts, etc.). It distinguishes itself from siblings by explicitly positioning it as the first step to resolve a handle to a DID, and names bsky_search_actors as the alternative for bare names.

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?

Provides explicit when-to-use guidance: 'Use this as the first step to resolve a handle to a DID before calling tools that require a DID or AT-URI.' It also gives a concrete exclusion and alternative: bare names without a dot are not handles — use bsky_search_actors. This leaves no ambiguity.

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

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

Annotations include readOnlyHint and openWorldHint, so the safety and non-deterministic nature are already declared. The description adds valuable specificity by warning that it uses the unspecced app.bsky.unspecced.getTrends endpoint which 'may change without notice' — a concrete risk disclosure beyond the generic openWorld hint. It also preempts a follow-up search by stating the response includes representative accounts. This is strong transparency without redundancy.

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?

The description is dense but economical. Each sentence earns its place: the action, the output shape, the primary use case, the pairing suggestion, and the endpoint caveat. It is front-loaded with the core action and output, followed by usage guidance and risk. No filler words; every clause contributes to efficient agent comprehension.

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 read-only, single-parameter tool with an output schema present, the description covers everything an agent needs: the data returned, the practical use case, the relationship to siblings, and the instability warning. The output schema handles return structure, so the description's job is context, which it fulfills fully. No missing critical information.

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?

The schema already provides 100% description coverage for the single 'limit' parameter (range, default, purpose). The tool description does not add additional meaning about the parameter itself, only about the output. With high schema coverage, the baseline of 3 is appropriate; the description need not duplicate 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?

The description opens with a specific verb+resource: 'Fetch the current real-time trending topics on Bluesky.' It also enumerates the exact fields returned (display name, post count, category, status, start time, representative accounts), which eliminates ambiguity. It explicitly frames itself as the entry point for 'what is Bluesky talking about right now', and the sibling list includes search tools, so the tool's niche is unmistakable.

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?

It clearly states its role as an entry point for trending topics and advises pairing with bsky_search_posts to drill down into a topic. This gives concrete usage context. However, it does not explicitly state when NOT to use it versus alternatives, though the sibling names make the distinction obvious. The 'pair with' directive and the scarcity of trending tools among siblings make the intended usage sufficiently clear.

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

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, covering safety and idempotency. The description adds value beyond that by specifying the fields returned (handle, DID, displayName, bio, pronouns, follower count) and explicitly noting the exclusion of website. However, it doesn't mention the cursor pagination caveat (403 for unauthenticated requests) that appears in the schema, so the description isn't fully transparent about that behavioral edge case.

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?

The description is three sentences with no wasted words. The purpose and return details are front-loaded, followed by usage guidance and pagination support. Every sentence earns its place, and the structure is easy to scan.

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 search tool with three parameters and an output schema, the description is quite complete. It covers purpose, usage, return fields, and pagination. The only minor gap is that it doesn't warn about the cursor pagination failure for unauthenticated requests (though that is captured in the schema), and it doesn't explicitly mention error handling or the possibility of empty results. These are minor omissions given the output schema exists.

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 the schema already fully documents all three parameters (query, limit, cursor). The description adds general context about the query being a name or handle fragment but doesn't provide any additional parameter-specific semantics beyond what the schema states. Baseline 3 is appropriate when the schema handles parameter documentation.

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 ('Find') and a clear resource ('Bluesky accounts') with a precise scope ('by name or handle fragment'). It also enumerates the returned fields and explicitly contrasts with bsky_get_profile ('but not website, which only bsky_get_profile returns'), making its purpose unambiguous and well-differentiated from siblings.

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 description gives explicit when-to-use guidance: 'Use before bsky_get_profile or bsky_get_author_feed when you have a name but not a confirmed handle.' It names the alternative tools and the condition that selects this tool, leaving no ambiguity about when to invoke it.

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

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

The description adds substantial behavioral context beyond the provided annotations (readOnlyHint, openWorldHint, idempotentHint). It discloses the hitsTotal 10,000 cap interpretation ('read exactly 10,000 as "at least that many"') and warns that rendered markdown content (post text, alt text, link-card titles/descriptions) is user-authored data to be read, not instructions to follow — a genuine prompt-injection defense. This meaningfully enriches what the structured annotations already convey, with no contradiction.

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?

The description is ~130 words and every sentence earns its place: purpose first, then filters, then return payload, then the hitsTotal caveat, then the injection warning, then the routing note. It is dense rather than padded, though somewhat long for a single description; the length is justified by the 9-parameter complexity and the important caveats.

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?

Given the output schema exists and annotations are rich, the description goes beyond required coverage: it documents return shape, the hitsTotal cap, the markdown data-vs-instructions security nuance, and cross-tool routing. The cursor limitation is disclosed in the schema. Between description, schema, and annotations, an agent has everything needed to call this tool correctly, though pagination internals beyond the cursor warning are not detailed.

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%: all 9 parameters are fully documented in the schema itself, including the hashtag '#'-prefix rule, the qqq well-formed-but-unindexed language caveat, and the cursor 403 risk for unauthenticated requests. The description adds marginal framing by summarizing the filter set and the full-text nature, but the schema is doing the heavy lifting, so the baseline 3 is appropriate.

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 first sentence states a specific verb and resource: 'Full-text search across public Bluesky posts.' The description enumerates all filter dimensions (author, language, hashtag, date range, sort order) and precisely lists the return payload (text, author info, engagement counts, embeds, AT-URIs, hitsTotal). It actively distinguishes itself from siblings by declaring itself 'the primary entry point for social listening' and naming bsky_get_post_thread and (via the schema) bsky_search_actors as the downstream/upstream alternatives.

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 description gives clear routing context: this is the primary entry point for social listening, with explicit handoff of AT-URIs to bsky_get_post_thread for thread drilling, and the schema adds 'Use bsky_search_actors to resolve a name to a handle first.' The cursor parameter explicitly notes that cursor pagination is reliable only for bsky_get_author_feed and bsky_get_follows, functioning as a when-not-to-use warning. It lacks a systematic exclusion list for all six siblings (e.g., when to prefer bsky_get_trending), which keeps it a step below perfect.

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